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TwinDad
29th Dec 2010, 02:23 PM
Been window shopping for a DSLR. Wishing mostly. Have a technical question of sorts.

My point&shoot has a 6x optical zoom. No idea what the focal length is. I just looked at a Nikon DSLR kit (waaaay over my budget) with a 200mm zoom lens that claims an 11x zoom.

So can somebody explain the relationship between focal length and zoom, and maybe a little about the trade-offs between zoom and straight telephoto lenses?

My main issue is there is frequently a railfan shot that I can't get physically close to. The 6x zoom on the P&S helps but I'd like to have more, and a better image anyway, but I know I won't be able to afford the really high soot telephoto stuff. So I'd like to understand the issues to make the best trade-offs.

Not that I'll be able to pull the trigger anytime soon.

kdk
29th Dec 2010, 02:51 PM
Well in the SLR DSLR world, a 50MM lens is "normal", so a 100 MM lens is 2X, a 200MM lens is 4X etc. But it gets complicated because the lower end DSLR's have a "cropped" sensor, so the lens magnification ratio is bigger. On a cropped sensor camera for the lens lenght you add one half of the lens length. So, on that entry level DSLR a 200MM lens is actually a 300MM lens, or 6X. A 50-200 zoom is really a 75-300 zoom, magnification wise. I have no idea where they get 11X from. As for the trade off's, a good zoom is fine unless your doing high end pro stuff and huge enlargements. If your not ready to buy I wont go any further :)

MooseID
29th Dec 2010, 03:11 PM
The zoom feature is used to change the focal length of the lense.

As the focal length increases the images appear closer to the camera.

As the focal length increases the depth of field also increases. The depth of field is the range at which the image is in focus. With a shorter focal length more of the foreground and background is out of focus. As an example if you use a 50 mm lense to make a portrait of your loved one, and you focus on the eyes it is possible that the ears and the tip of the nose will be out of focus. The best lense for portrait photos is about 80 mm focal length. A 35mm to 100 mm zoom lense with manual focus is a good choice for general photography and snap shooting. The reason I recommend a manual focus lense is because autofocus lenses do not always line up on the subject as you want it to.

In the view screen of most cameras the entire image is always in focus. Therefore, the upper quality cameras have a Depth of Field Preview feature which you can use to see what is actually in focus on the recorded image.

For long range telephoto shots a 100mm to 200mm zoom lense is good for hand held shots. Anything over 200 mm should be solidly mounted on a tripod to prevent blurred images due to microshaking of your hands and shutter bounce.

Digital cameras also have what is called digital zoom. This does not bring the image closer to the camera. All it does is crop the image and enlarge it to the view screen. consequently the image quality suffers from low pixel count.

There may be better cameras on the market, but Nikon has been the industry standard that all other cameras are compared to. The best testimonial to that is the fact that National Geographic Magazine's photographers all use Nikons. There are some who will recommend Canon cameras for good reasons. They make great cameras also.

If you have more questions....ask them.

kdk
29th Dec 2010, 03:36 PM
The zoom feature is used to change the focal length of the lense.

As the focal length increases the depth of field also increases. .

Actually its the opposite, the most DOF is attained at short focal lengths.

nutrakusr
29th Dec 2010, 03:43 PM
Correction. As focal length increases, depth of focus decreases. Wide angle lenses (less than 50mm focal length) have very wide depth of focus. They sometimes don't have to be focused and practically everything is in focus. With telephotos you have probably seen photos of wildlife where the animal is sharp and everything else is out of focus, making the subject standout. This is due to the very shallow depth of focus. Portrait lenses are best in the 85 to 100mm range because they provide adequate depth of focus without distortion of the image. When used to photograph people, they are used at sufficient distance to provide depth of focus that covers the whole head front to back without distorting the nose, such as a wider angle lens would do.

TwinDad
29th Dec 2010, 05:40 PM
Good answers so far. Thank you.

On one specific point. My pont & shoot has a 6x optical (not digital - I never use digital) zoom. What you're saying is that to get an equivalent "bring that boxcar closer to me" from a DSLR lens I need at least a 300mm focal length. BUT on the lower end DSLR because of the way the sensor is cropped I might get away with a 200mm lens.

Is that right?


How do i know if the sensor is cropped on a particular model?

jmodule
29th Dec 2010, 05:50 PM
I think kdk is correct that a 200mm lens on a Nikon is around 6x. If you're looking mainly at optical magnification, the most affordable option is probably a so called super-zoom point-and-shoot camera (see this article (http://www.pcmag.com/article2/0,2817,2327846,00.asp) in PC Mag for some examples). Otherwise if you had a DSLR already I would suggest looking into renting a telephoto lens, as they are too expensive to purchase for casual use.

That said, the Nikon 55-200 with image stabilization is said to be a good deal for the money. With the bigger sensor on the DSLR, you might be able to crop tightly on your computer enough to mimic a longer telephoto and still have a good quality image.


How do i know if the sensor is cropped on a particular model?

It's kind of the opposite. All Digital cameras are "cropped" compared to film cameras unless it specifically says "full frame" and usually you only find those on the Pro level DLSRs.

BryanC (RIP)
29th Dec 2010, 05:56 PM
If we are going to get into the arena of DSLR "wannabes" then I have to suggest my Fujifilm SD2500HD http://www.nscale.net/forums/showthread.php?19751-The-Fujifilm-S2500HD-Camera

I couldn't be happier with it and a very reasonable price!

Edit: BTW, that PC Mag article is missing some very viable contenders! (Maybe it is dated?)

dlr1957
29th Dec 2010, 06:54 PM
There are a number of things that effect depth of field. Lens focal length is one and has already been discussed. The other major thing that effects depth of field is aperture, or size of lens openning that light passes through. It is also sometimes called f-stop. If you see it listed it often times has an "f" in front of it, f2.8 or f22. In general the larger the lens openning (the lower the f number) the less depth of field, the smaller the lens openning (the greater the f number) the greater the depth of field. It is not unusual for a zoom lens to change the maximum available lens openning as focal length changes.

How do i know if the sensor is cropped on a particular model?
Normaly the camera specifications will tell you sensor size. Full frame usually indicates a sensor that aproximates a 35mm film size of 35x24mm. APS-H (used in some canons I think) is 28.7x19mm, APS-C is probably the most common of the smaller sensors and varys in size 23.6x15.7mm and 22.2x14.8 are popular. Thanks to the Wikipedia for the sensor size information.

Dave

Dennis R
29th Dec 2010, 10:25 PM
How do i know if the sensor is cropped on a particular model?

The Nikon DSLR's are sensor cropped (DX)with the exception of these models: D700 and the D3xxx series. These models are
full frame (FX) like the older 35mm SLR cameras. A 50mm lens on a D700 or D3xxx will actually be 50mm while on all other
Nikon DSLR models it would be 75mm with the sensor cropping (DX). The full frame models are usually quite a bit more in price than the
DX models.

Note: The D300 and D300s are not in the D3xxx group. They are both cropped (DX). The D3xxx grouping is the D3, D3S, and the D3X. I think
I got them all.

Sherman
29th Dec 2010, 10:35 PM
TD,

When camera makers say "6x zoom" they mean the longest focal length of the lens is 6x the shortest focal length. You didn't give the shortest focal length of that 200mm zoom. If the longest focal length is 200mm and it is truly an 11x zoom then the shortest focal length would be 18mm. (Just divide 200mm by 11.)

As stated in a previous post most DSLRs have sensors smaller than a 35mm film frame, typically resulting in a 1.6 magnification factor. (It really isn't magnification, just a change in the field of view.) So if that Nikon lens is an 18-200mm zoom and the DSLR you were looking at has a 1.6 factor then the lens would give the same basic view as a 29-320mm zoom on a 35mm film camera (or a DSLR with a "full-frame" sensor). That is a pretty nice zoom range that would cover most photographic situations.

--Sherman

kdk
29th Dec 2010, 11:20 PM
Good answers so far. Thank you.

On one specific point. My pont & shoot has a 6x optical (not digital - I never use digital) zoom. What you're saying is that to get an equivalent "bring that boxcar closer to me" from a DSLR lens I need at least a 300mm focal length. BUT on the lower end DSLR because of the way the sensor is cropped I might get away with a 200mm lens.

Is that right?

Thats correct Twindad


How do i know if the sensor is cropped on a particular model?

You would need to do a little research Twindad but, Nikon calls it a "DX" sensor, the cropped sensor, verses an "FX" sensor, but basically, if you dont spend over 2000.00 for just the body your going to get a cropped sensor.

TwinDad
29th Dec 2010, 11:26 PM
Keep in mind - I'm not shopping, and won't be any time soon. All of this stuff is WAY out of my budget. But I'm dreaming, and trying to understand.

So the Nikon I semi-randomly chose was a package deal of a D700 (12.1MP FX format sensor) and a Nikon AF-S DX Nikkor 18-200mm f3.5-f5.6 zoom lens (good guess, Sherman).

The camera in my hand is a Canon PowerShot A710 (7.1MP sensor) with a "6x zoom lens" - here's where it gets confusing. the front of the lens case says: "5.8-34.8mm 1:2.8 - 4.8" ... but a check at www.dpreview.com (http://www.dpreview.com/reviews/specs/Canon/canon_a710is.asp) says that its effective zoom range is 35-210mm f2.8-4.8. I'm guessing the review site is giving the effective focal distance range after the DX-ish cropping of the sensor?

The same review site gives a "35mm equivalent focal length (APS-C)" for the Nikon LENS (http://www.dpreview.com/lensreviews/nikon_18-200_3p5-5p6_vr_afs_n15/) of 27-300mm, a maximum aperture of f3.5-5.6 and a minimum aperture of f22-36.

OK, I have no idea what APS-C means... but it also says the maximum format size is "DX"... I expect this means that if you plug this guy into an FX format camera body like the D700, the LENS is going to crop the image for you (or force the camera to do it or whatever).

So looking strictly at my "bring that boxcar closer" metric... let's say the boxcar appears to be 1000 feet away through the Nikon lens at the 27mm wide angle view. If we say the Nikon lens's 27mm wide angle as "1:1", then...


The Canon wide angle shot would be at about 1:1.3 (35mm/27mm) - the boxcar will appear to be about 770 feet away (close to its actual distance, coincidentally)
The Canon zoom shot would be at about 1:7.77 (210mm / 27mm) - the boxcar will appear to be about 129 feet away
The Nikon at full zoom would appear at 1:11 (300/27) - the boxcar will appear to be about 90 feet away.

Now, to put this in real terms... in order to get that same "90 feet away" shot from my Canon, I have to get... 300 ACTUAL FEET CLOSER to the subject, yes? (90 * 7.77 ~= 700, while 90 * 11 ~= 1,000). Or flipped around I can get the same shot in the Nikon from 300 feet farther away...


Right?

Nevermind how much better it would look due to the better optics, sensor, and so on with the higher-zoot camera set.

And I'm guessing based on remembering using dad's camera, that much over about 300mm the lenses get in the "rent it" range due to size and cost... (the Canon L-series 500mm telephoto weighs 8.5 lbs and costs $7,000 at Best Buy... I don't think so...)

And yes, BryanC, I will look at the Fuji. Though I'm a bit of a Canon fan - my dad has had them since I was a kid.

Dennis R
30th Dec 2010, 12:23 AM
The same review site gives a "35mm equivalent focal length (APS-C)" for the Nikon LENS of 27-300mm, a maximum aperture of f3.5-5.6 and a minimum aperture of f22-36.

OK, I have no idea what APS-C means... but it also says the maximum format size is "DX"... I expect this means that if you plug this guy into an FX format camera body like the D700, the LENS is going to crop the image for you (or force the camera to do it or whatever).


TD, the APS-C refers to the sensor format of 25.1 X 16.1mm which is DX on a Nikon. The 18-200 will not be cropped on a D700 so you will not get the 300/27. Also, a DX lens on a D700 will decrease the photo down to 5MP instead of the normal 12.1MP size. The photo would still have good quality however. Vignetting (black edges) will also occur at certain focal lengths.

TwinDad
30th Dec 2010, 12:43 AM
TD, the APS-C refers to the sensor format of 25.1 X 16.1mm which is DX on a Nikon. The 18-200 will not be cropped on a D700 so you will not get the 300/27. Also, a DX lens on a D700 will decrease the photo down to 5MP instead of the normal 12.1MP size. The photo would still have good quality however. Vignetting (black edges) will also occur at certain focal lengths.

Interesting... so if I put the 18-200 lens on a D700, I get 18-200 and half the MP, but if I put it on a DX body, I get 27-300 and all the MP. Presumably a good argument for using the (higher quality/price?) FX capable lenses on the D700, or a (cheaper?) DX body on this lens?

My head is swimming... :eek:

Dennis R
30th Dec 2010, 01:02 AM
TD, not all the FX lens are more expensive. There are some very high quality FX lens that are cheaper than some of the DX lens. The 50 1.8 ($120), 70-300 VR (500-600), the 60mm macro (550), plus others are all excellent FX lens and will work on both FX and DX. They would all still be cropped on DX body. A 17-55 DX lens sells for about $1400.00, a very high quality DX formatted lens.

TwinDad
30th Dec 2010, 01:16 AM
So... umm... can y'all explain this FX vs. DX thing a little more? How exactly is the image cropped? Is it done with some kind of mechanical aperture, or in software, or by shutting down part of the CCD? What are the side effects and trade offs? What's going on here?

Sherman
30th Dec 2010, 05:34 PM
TD,

The smaller sensor is the DX sensor, the "full-frame" sensor is the FX sensor. Full-frame refers to the sensor being the same size as a frame of 35mm film.

The lens situation works like this- a lens projects an image circle on the film or digital sensor. Since the DX sensor is smaller the lens only needs to cover that sensor size, so a DX lens would have an image circle just slightly larger than the diagonal dimension of the sensor (slightly larger to avoid light fall-off in the corners that would cause vignetting). An FX lens needs to cover the full-frame sensor so it has to have a larger projected image circle. All things being equal (and they rarely are) a lens with a larger image circle is more expensive. It is more difficult to design say a 100mm lens with an image circle of 40mm than one with an image circle of 29mm.

Now take it the next step- if you put a DX lens on an FX camera the lens will not illuminate the entire sensor (since the DX lens has a smaller image circle than the FX sensor's diagonal measurement). So you get a "cropped" image; actually an image that is vignetted on either end.

My digital system is Canon and they have the same setup, EF lenses project an image circle large enough to cover a full-frame sensor, EF-S lenses project a smaller image circle. With Canon cameras you can mount an EF lens on either a full-frame camera or a smaller sensor camera since the EF lens will cover both sensors. However you cannot mount an EF-S lens on an EF sensor-sized camera since it won't cover the larger format. I'm surprised that Nikon lenses will mount either way.

And yes, when you look at the review of your camera and it says the effective zoom range is 35-210mm it is expressing the zoom range as a 35mm or full-frame equivalent. It is the best way to compare the focal lengths of cameras that have vastly different sensor sizes.

--Sherman

TwinDad
30th Dec 2010, 09:19 PM
Apparently you can't double-thank a post. If I could, I would. Lightbulbs coming on all over the place now.

So... What aboutthe focal length/zoom question? Am I right that I would need to get 300 feet closer to my boxcar with the 200mm vs the 300mm?

Sherman
31st Dec 2010, 10:22 AM
TD,

How much closer you need to get depends on how far away you started in the first place. Keep in mind that the focal length number 200mm, 300mm etc. doesn't have anything at all to do with the distance to the subject. The things to consider are "angle of view" and "field of view". A 200mm lens on a 35mm camera has an angle of view of about 10.1 degrees. A 300mm lens has an angle of view of about 6.5 degrees.

At 300 feet from your subject a 200mm lens on a camera with a 1.6 multiplier has a field of view of 33.80 feet. On the same camera at the same distance a 300mm lens has a field of view of 22.5 feet. To get the same image with the 200mm that you got with the 300mm you would need to be 200 feet away.

Here's a site with some useful photo calculators.
http://tawbaware.com/maxlyons/calc.htm

--Sherman

TwinDad
31st Dec 2010, 11:31 AM
TD,

How much closer you need to get depends on how far away you started in the first place. Keep in mind that the focal length number 200mm, 300mm etc. doesn't have anything at all to do with the distance to the subject. The things to consider are "angle of view" and "field of view". A 200mm lens on a 35mm camera has an angle of view of about 10.1 degrees. A 300mm lens has an angle of view of about 6.5 degrees.

At 300 feet from your subject a 200mm lens on a camera with a 1.6 multiplier has a field of view of 33.80 feet. On the same camera at the same distance a 300mm lens has a field of view of 22.5 feet. To get the same image with the 200mm that you got with the 300mm you would need to be 200 feet away.

Here's a site with some useful photo calculators.
http://tawbaware.com/maxlyons/calc.htm

--Sherman

Thanks, Sherman. You explain things well. That's pretty much the effect I was asking about, only explained more correctly AND more concisely. And it confirms what I was thinking.

Let me rephrase myself one more time and speak this back to you to make sure I really do understand what you're saying.

Being a little soft with the precise numbers... what I think you're saying is that all other things being held equal, the distance at which I get the same field of view with two lenses (or two zoom settings on the same lens) is roughly the ratio of the focal lengths... I can get the same shot at 150% of the distance with 300mm vs. 200mm. Or conversely, at the same subject distance the difference in field of view is also the ratio of the focal lengths... all other things being held equal.

If I'm taking a picture of a boxcar, and I want to fill the frame with the boxcar (couplers at the edge of the image, let's say). And let's say that I can get that shot at 300 feet with the 300mm lens. The net effect is that I would need to hike 100 feet closer to get the same shot with the 200mm lens, all other things being equal. Or, at the same distance, I'd get my boxcar, plus half of the next one in the train with the 200mm lens.

Sherman
31st Dec 2010, 04:09 PM
You've got it. At least for 200mm and 300mm focal lengths. Actually the ratio pretty much holds true for any focal length longer than "normal" which is usually considered to be somewhere between 40mm and 55mm with full-frame sensors.

At the wide end of things a relatively small change in focal length produces a much more noticeable change in perspective but those small changes represent a larger percentage of the focal length being changed. (The difference between the FOV of a 28mm lens and a 24mm lens, again full-frame, is very noticeable even though it is only 4mm. But 4mm is a relatively large percentage of 24 or 28.)

--Sherman

TwinDad
31st Dec 2010, 05:41 PM
You've got it. At least for 200mm and 300mm focal lengths. Actually the ratio pretty much holds true for any focal length longer than "normal" which is usually considered to be somewhere between 40mm and 55mm with full-frame sensors.

At the wide end of things a relatively small change in focal length produces a much more noticeable change in perspective but those small changes represent a larger percentage of the focal length being changed. (The difference between the FOV of a 28mm lens and a 24mm lens, again full-frame, is very noticeable even though it is only 4mm. But 4mm is a relatively large percentage of 24 or 28.)

--Sherman

Thanks, Sherman. Since my interest is mostly in getting "up close" with things that are farther away than I like, it's mostly the telephoto end of things that I'm concerned with. I just wanted to understand intuitively how much better (in that one regard) the lenses available for DSLRs would be than the lens I already have. And then that whole bit with "cropping" confused me, but you sorted that.

I think I'm good for now... I'll probably be confused about more stuff once I actually start shopping... someday... when I hit the lottery... :(

hallm
2nd Jan 2011, 05:47 PM
TwinDad

You have posted some interesting questions and received some great information in response.


Sometimes the type of photography you want to do can help you to decide what features the camera and lenses must have in order to get the results you want. In my case I wanted to shoot inside sports that my children were playing such as hockey, basketball, and volley ball. In some leagues flash photography is prohibited and this means that my equipment had to be able to function in low light conditions, without the use of a flash, and yet still be able to capture fast motion without blurring the players. This type of equipment comes with I high price tag and might be overkill for some other applications.

Five years ago I replaced my AE1 Canon film camera with a digital Nikon D50. The digital technology back then for ‘point and shoot’ cameras was more like 'point and wait' which was a poor choice for sports shooters. My newer D300 is much better in its low light (ISO) capabilities over my older D50 and certainly the D700 is on my wish list. The other thing to consider is the type and quality of lenses (prime Vs telephoto) as well. Camera bodies come and go but your investment in lenses will never be regretted


While the web is a great resource for information one text that you might find useful in explaining basic photography fundamentals is a book by Bryan Peterson called Understanding Exposure. You might find it an interesting read.


Mike

http://www.amazon.com/Understanding-Exposure-3rd-Photographs-Camera/dp/0817439390/ref=sr_1_1?ie=UTF8&qid=1294002267&sr=8-1#_

Chessack
5th Jan 2011, 01:00 AM
Some things to think about:

There are two kinds of lenses (those with internal motors, and those without), and they don't all work with all bodies. The cheaper DSLRs don't have a motor in the camera body, and will only work with the lenses that have their own motors. Nikon calls these "DX" lenses.

Also, sometimes you can get lenses of similar focal length with different prices. The more expensive ones are the more highly corrected ones with the least imperfections.

Some of what you need will depend on what you plan to do. If you're planning on doing a lot of indoor shooting, you'll need smaller focal lengths or maybe even a macro lens. I use my 50 mm portrait lens or, more often, my 60 mm macro lens to shoot my model RR layout, and those are actually both too "big" -- I really need more of a wide-angle lens like a 25 mm or so to shoot the layout because my room is not very big and I can't get back very far (and because my D90 is not full frame, which magnifies the image even more).

On the other hand if you plan to do a lot of outdoor shooting, of things like nature and especially animals such as birds, you'll need some serious telephoto power... even my 70-300 mm zoom on full telephoto is not really enough to get good bird shots (but it's what I can afford right now, since the 400+ mm lenses are insanely expensive and I'm not going to spend as much on my camera equipment as I spent on my car!).

You can also get less expensive but still acceptable lenses from third parties. Outdoor Photographer magazine frequently sings the praises of Sigma and Tamron, both of which will tend to run you a bit less than Nikon or Canon, and both of which make lenses fully compatible with those bodies (though, I have not personally bought anything but Nikon yet).

Finally I want to agree with Mike.. bodies come and go, but a good lens will always be a good lens. All 3 of my lenses (50 mm f/1.8, 60 mm macro, and 70-300 mm zoom Nikkor lenses) were bought with my old film N90 between 2000 and 2007. I can use all of them just fine with my D90, and they'll basically last forever as long as I keep them safe and treat them right.

C

TwinDad
5th Jan 2011, 09:33 AM
Thanks for the responses, all... and for the book reference, Mike (and welcome to the site, BTW!!)

As I've mentioned, it will likely be a LONG while before I actually do anything. Camera gear is necessarily expensive (though there are bargains to be had), and it's pretty low on the priority list on a very tight hobby budget (behind things like track and DCC...).

What I envision doing is basically two things: close-up shots of my models, and railfan shots or landscapes. Which are, of course, fairly mutually exclusive areas. Nice that the better stuff has changeable lenses. And most of that for online consumption, not print. I don't expect to be chasing birds, and probably not a whole lot of high speed, low light sports, at least not right off.

I expect I would probably look for a good quality 70-300 ish zoom and a matching wide-angle zoom (28-80 ish) to pretty much cover all the bases. This combo has served my dad well for decades in most situations. I might get a little more specific for the model shots with a fixed focal length wide angle lens if the wide zoom doesn't seem to be cutting it.

They may not stand up to "pro" standards, but I'm actually fairly satisfied with the results I get with my P&S Canon. Can I do better? Sure. But probably not with the $$$ I can afford to allocate right now. Someday, yes!! The main thing that has me dissatisfied is with the zoom range (hard to get "close up" shots of stuff without trespassing), and frankly I probably can't afford a lens that would do that anyway.

So I window shop and I dream and I ask questions... :D :D

Chessack
5th Jan 2011, 02:46 PM
A 28-80 and a 70-300 is a good choice. In fact I've been toying with getting something like a 28-80 myself.

One word of caution: if you plan on going handheld, even the smaller zooms are probably going to be too big to avoid "camera shake" in your images. I only do handheld with my 50 mm portrait lens (because it's tiny). Even the 60 mm macro needs a tripod. So if you want to do a bunch of handheld work with the smaller lens focal lengths, you might be better off getting a few different, smaller, lighter, lenses, rather than a bigger, heavier, camera-shake-inducing zoom.

C

spiralcity
26th May 2011, 10:41 AM
I havent posted in some time and im sure this is an old thread. I just want twin to know that you can use old screw mount manual focus lenses with great results at a fraction of the price auto lenses. Check out http://forum.mflenses.com/ and talk to the photographers their, be sure to check out the outstanding photos that are produced from these old lenses.

spiralcity
27th May 2011, 11:40 AM
Twin, I have a blog about photography. It's actually a free course about the subject. http://spiralcityphoto.blogspot.com/search?updated-min=2009-01-01T00%3A00%3A00-06%3A00&updated-max=2010-01-01T00%3A00%3A00-06%3A00&max-results=12

TwinDad
27th May 2011, 11:53 AM
Twin, I have a blog about photography. It's actually a free course about the subject. http://spiralcityphoto.blogspot.com/search?updated-min=2009-01-01T00%3A00%3A00-06%3A00&updated-max=2010-01-01T00%3A00%3A00-06%3A00&max-results=12

Cool! Thanks. I can see I'll be spending some time on that blog... :D

Jimmi (RIP)
30th May 2011, 02:48 PM
spiralcity,
My thanks also for that link. I'll be checking it out too.

ibm650
4th Oct 2011, 01:02 AM
Superzooms are great for outdoor shots, indoor they tend to be slow. They work by having a much smaller sensor size, thus they tend to be slower (ie need more light).

Arved
5th Oct 2011, 12:56 PM
Well in the SLR DSLR world, a 50MM lens is "normal"...

Not quite. You're forgetting the 1.5x "crop factor" of DX (APS-C) size sensors. Actually, this is 1.5x for Nikon, and 1.6x for Canon. So a 50mm lens in 35mm land has an equivalent focal length of 75mm (unless you're using an FX or "full frame" dSLR, like the Nikon D700, D3 series, Canon 5D series, etc).

So a "normal" focal length for a DX series camera is about 30mm. Give or take.

One of the problems with a dSLR is you need a long focal length to get far enough away so that you're not right on top of your model when photographing. It's very easy to have the lens shade out the pop-up flash, for instance. Although I have dSLRs (I'm a professional wedding and portrait photographer), I'm actually considering getting something a bit smaller for my model photography. There are a lot of advantages to using smaller cameras for macro photography - beyond the scope of this discussion, though.

- Arved

capnvic
25th Oct 2011, 04:30 PM
So lets say I am stupid, I come from the old school of photography. I have A Fuji S3 12.1 MP DSLR and I have a Micro nikkor 55mm AF-D lens. so at 15 ft, depth of field would be 31ft approx, at F22. I understand that the better the aperature setting the better the depth of field. Thus the problems with zoom lenses vs fixed focal length lenses because the depth of field becomes compressed, and on digital camera, it is possible at greater aperature settings for vignetting? I was thinking of buying a used Fuji S3, since it is very much like my Nikon N70.

Arved
26th Oct 2011, 10:22 AM
Note: The D300 and D300s are not in the D3xxx group. They are both cropped (DX). The D3xxx grouping is the D3, D3S, and the D3X. I think
I got them all.

Neither is the D3000 (http://www.nikonusa.com/Nikon-Products/Product/Digital-SLR-Cameras/25462/D3000.html) or the D3100 (http://www.nikonusa.com/Nikon-Products/Product/Digital-SLR-Cameras/25472/D3100.html). I wouldn't have said D3xxx. I would have said the D3 series cameras.

Don't worry about full-frame (FX) or "cropped sensor" (DX or APS-C) size sensor. for 99% of the photographers out there, this is meaningless. Big advantage to full frame cameras is when shooting ultra-wide angle and fisheye lenses, and in rediculously high sensitivity (ISO) ranges (ISO 128,000 anyone?)

The "11x" zoom you are looking at is the 18-200mm zoom lens. if you devide 200 by 18, you'll see where the 11x comes from. This is a "do everything" wide angle to telephoto lens. The wide zoom range forces some compromises in terms of overall lens sharpness and light gathering capability.

Two decent reviews of this lens. One by Ken Rockwell (http://www.kenrockwell.com/nikon/18-200mm-ii.htm), a wanna-be expert who many ammatures listen to, and another by a real pro, Thom Hogan (http://bythom.com/18200lens.htm). There have been some reports of this lens being a bit soft. This might be from people with too high expectations, or it may simply be sample variation. Try it out, if you don't like it, return it for another lens, and if that proves not to be up to your standards, choose another lens with a less zoom range, like the 18-105 if VR is important to you, or the 18-135 if VR is not. If you've got steady hands, and good handholding technique, VR isn't that important. A monopod (http://en.wikipedia.org/wiki/Monopod)makes a good "poor man's VR." VR is more important for low light and longer telephoto lenses.

Hope this helps,
- Arved

Sundiesel
21st Nov 2011, 02:38 PM
I'm new to this forum and being an ex-professional photographer (Navy, Public Service, Newspapers & Private Enterprise) I am a little interested in this subject.
My training in photography however, is limited to the pre-digital era, so I suppose I'm now classed as something of a dinosaur.
Anyway, should any of you be looking for a good all rounder camera for our hobby, I think I've found it.
When I was looking around for a new camera to replace my old DSLR, I automatically thought, "another DSLR". Then I looked at their price and immediately decided I should look instead, at secondhand equipment. Even then, came the realization, I just couldn't afford one. Not right now.
So I started looking at the new crop of Ultra Zoom (UZ) cameras....a fraction of the cost of a DSLR and 3 lens outfit.
After doing quite a bit of research, I narrowed my search down to 3 cameras on my short list and eventually ended up with a "Sony Cybershot HX100V" camera.
Its incredibly flexible with an amazing focal range (27mm to 810mm) through a German, Carl Zeiss lens and it's able to take macro (close up) photos too. All with the one lens.
In the past, because they use the same sensors, UZ's have been classed with "compact" cameras, regarding image quality and the mindset is that if you want superior image quality you must use a DSLR.
Well not any more. According to reviews, these HX100V's are producing excellent images, right across the zoom range. I wouldn't have bought one if they didn't.
The beauty of these UZ cameras is that when in the field, you don't need to be carrying extra lenses, just in case you need one or another for that one brilliant shot. All the lenses you'll need are built into the one camera.
After 41 years of clicking shutters, this would be, without doubt, the most versatile camera I have ever used......and I own it.
So, to sum up, this camera is ideal for me because of...........
* Price
* Versatility
* Image quality
Should you be looking to buy a new camera, and like me, can't afford a new, or even used, DSLR, my recommendation is to look at the current range of UZ cameras as an alternative to DSLR's.
But do some research into which brand and model best suits you. However, please study the reviews very carefully, as some of the cameras on the market are still the older generation and have troubles with lens aberations when the zoom is a long way out or really wide. Also, some manufacturers still use older style sensors and the image quality isn't brilliant.
On the whole though, UZ's are improving in leaps and bounds and I'm very happy with the one I bought.
Cheers,
Rob