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06-19-2010, 09:54 PM   #706
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QuoteOriginally posted by 8540tomg Quote
Do you really get that much more with the more expensive glass? Thoughts?
In my opinion no.

Picasso with a pencil and a sheet of typewriter paper is going to turn out better images than I could with a well equipped art studio.

I did notice that one of your pics had a yellow color cast on my monitor. Color cast can soften the perception of color and contrast. I changed it to what I think is a more accurate WB. I hope you don't mind. Seems like an excellent shot otherwise. Maybe you are being too hard on yourself. It takes time to sort out what gear can and cannot do.

Also I'll throw in this Hummer shot taken with a 180 buck Sigma zoom a la Marc.


Last edited by wildman; 07-30-2010 at 07:22 PM.
06-20-2010, 04:13 AM   #707
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Thanks for the thoughts Marc/Wiildman,

I'm not displeased with the M 400/5.6 by any means. I'm getting shots I never got before with shorter lenses and I'm enjoying the process. I'll keep plugging away with it and experimenting with different times of day and subjects. That being said I can't help but feel low dispersion glass and other techinical advances over the past 30 years have resulted in better optics. The grass is always greener on the other side of the fence - right?

Tom G
06-20-2010, 05:48 AM   #708
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QuoteOriginally posted by 8540tomg Quote
That being said I can't help but feel low dispersion glass and other techinical advances over the past 30 years have resulted in better optics.
I agree with that especially with backlighting and strong sunny days with deep shadows an APO glass is noticeably better than an achromatic.

Looking at your excellent female RWBB made me think of this one. I was deep in the bottom land of the Mississippi in an abandoned hunter's blind waiting for Yellow-headed BBs to come along. Instead this lady came. She didn't seem afraid just curious and stayed with me for over an hour getting closer and closer.

560mm, 1/200 ISO 100 cropped

Last edited by wildman; 07-30-2010 at 07:22 PM.
06-20-2010, 06:25 AM   #709
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QuoteOriginally posted by 8540tomg Quote
I can't help but wonder how different these images might be if they were taken under the same conditions with an A 400/2.8 for instance. Thoughts?
FWIW, Tom, I can't help but wonder how much better my A*400 f2.8 photos might be if I were up to your skill level.

06-20-2010, 10:40 AM   #710
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QuoteOriginally posted by wildman Quote
I agree with that especially with backlighting and strong sunny days with deep shadows an APO glass is noticeably better than an achromatic.

Looking at your excellent female RWBB made me think of this one. I was deep in the bottom land of the Mississippi in an abandoned hunter's blind waiting for Yellow-headed BBs to come along. Instead this lady came. She didn't seem afraid just curious and stayed with me for over an hour getting closer and closer.

560mm, 1/200 ISO 100 cropped
Nice shot Wildman. The female RWBB will come quite close especially if she has a nest in the vacinity. Very good mothers these birds.

Excellent points re: sunny days and strong backlit issues. Time and a lot of poor images have taught me to avoid these situations with the M 400/5.6. You can get good shots but you have to pick your spots.

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06-20-2010, 10:42 AM   #711
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QuoteOriginally posted by dadipentak Quote
FWIW, Tom, I can't help but wonder how much better my A*400 f2.8 photos might be if I were up to your skill level.

Thanks Dave. I appreciate the comment. We do the best we can with the gear we have.

However you are being a bit modest. A quick look through your portfolio reveals a number of very fine A 400/2.8 images. I'm more than a little jealous of that particular piece of your arsenal.


Cheers

Tom G

Last edited by 8540tomg; 06-20-2010 at 01:46 PM. Reason: typo
06-21-2010, 09:47 AM   #712
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QuoteOriginally posted by wildman Quote
They are lovely birds whatever they are. Was the grouse taken in the South of India? I would think a grouse, at least here in the states, is pretty much limited to cold climates. Perhaps taken at a high altitude? Other than the front range of the Himalayas I think of India as being desert, tropical or subtropical. My understanding of Indian geography is probably flawed.

Focal length vs DOF:
So far as I have seen, all else being equal, for any given image scale DOF does not change with FL.

That is a pic taken with a 50mm at 50 feet will have the same DOF as a picture at 100 feet taken with a 100mm lens. Thus the 1000mm shot was taken at 5x the distance as the 560mm so more apparent DOF in the 1000mm shot.

Magnification does not change perspective so far as I know.
Wildman, the grouse is taken in Southern India. In Western Ghats. About 1000+ meters altitude. I have even seen them even at lower levels.
No deserts in the southern part of India. The only desert is the 'Thar' desert which in the northern part. Just below the Himalayas.
As to the depth/fl, if all else being the same, like aperture, shutter speed, will the DOF be the same for all focal lengths?
06-21-2010, 11:18 AM   #713
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QuoteOriginally posted by siva.ss.kumar Quote
Wildman, the grouse is taken in Southern India. In Western Ghats. About 1000+ meters altitude. I have even seen them even at lower levels.
No deserts in the southern part of India. The only desert is the 'Thar' desert which in the northern part. Just below the Himalayas.
As to the depth/fl, if all else being the same, like aperture, shutter speed, will the DOF be the same for all focal lengths?
I have always found that my long telephotos have very shallow Depth Of Field( part of photo that is in focus) while my wide angles have wonderful DOF. You can adjust DOF somewhat with aperture settings and shutter but the lens has a large effect on DOF. I am not sure I explained that well but others should be able to help with it.

06-22-2010, 12:09 AM   #714
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QuoteOriginally posted by siva.ss.kumar Quote
Wildman, the grouse is taken in Southern India. In Western Ghats. About 1000+ meters altitude. I have even seen them even at lower levels.
No deserts in the southern part of India. The only desert is the 'Thar' desert which in the northern part. Just below the Himalayas.
As to the depth/fl, if all else being the same, like aperture, shutter speed, will the DOF be the same for all focal lengths?
Western Ghats - You are fortunate to be so close to this region. My wife informs me that this area is one of the most bio-diverse areas of the world.

It is a small world. My wife was a guest lecturer at the University of Pune in field biology for a short time many years ago.

DOF:
I don't want to be too dogmatic about this.

Based on my experience I don't see any significant difference in DOF if FL length is the only factor and the subject is at the same apparent distance.

Case in point;
Two shots one taken very close up (about a foot?) with a FA35mm and the other taken with my 560mm, plus extension to bring the focus closer, at about 15 feet or so. Both about the same size on the same bush. The only difference is FL and distance between the lens and the subject. However, and I don't know how much difference this makes, but the 35mm was at f5.6 while the scope has a fixed wide open aperture of f7.

As matter of fact I have a Sigma 105mm macro but find the 560mm is better on butterflies than the 105mm because I can track their abrupt random movement better on the scope with the gun sight mounted on it. After all for any given lateral movement of the subject the angular movement is much smaller on the scope at 15 feet than on the 105mm at 12 inches.

Anyway take a look at these pics. Darned if I can see any significant difference in DOF between the two given the huge difference in FL.

If anyone else has any other theories about this I'm willing to listen.

Last edited by wildman; 07-30-2010 at 07:22 PM.
06-22-2010, 08:02 AM   #715
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QuoteOriginally posted by wildman Quote
Western Ghats - You are fortunate to be so close to this region. My wife informs me that this area is one of the most bio-diverse areas of the world.

It is a small world. My wife was a guest lecturer at the University of Pune in field biology for a short time many years ago.

DOF:
I don't want to be too dogmatic about this.

Based on my experience I don't see any significant difference in DOF if FL length is the only factor and the subject is at the same apparent distance.

Case in point;
Two shots one taken very close up (about a foot?) with a FA35mm and the other taken with my 560mm, plus extension to bring the focus closer, at about 15 feet or so. Both about the same size on the same bush. The only difference is FL and distance between the lens and the subject. However, and I don't know how much difference this makes, but the 35mm was at f5.6 while the scope has a fixed wide open aperture of f7.

As matter of fact I have a Sigma 105mm macro but find the 560mm is better on butterflies than the 105mm because I can track their abrupt random movement better on the scope with the gun sight mounted on it. After all for any given lateral movement of the subject the angular movement is much smaller on the scope at 15 feet than on the 105mm at 12 inches.

Anyway take a look at these pics. Darned if I can see any significant difference in DOF between the two given the huge difference in FL.

If anyone else has any other theories about this I'm willing to listen.
Great shots, Wildman! I'll have a look in my lens books from the dawn of history (well, the 1970's and 1960's anyway) and see how this works out. I suspect that you are correct that at the same subject size, the DOF is probably the same or close to it.
06-22-2010, 10:25 AM   #716
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Wow, Wildman, I rarely comment on posted shots but all these are just fantastic. You clearly have a much higher skill set than I currently possess, though I'm having a lot of fun trying to get there!
06-22-2010, 10:42 AM   #717
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Depth of field

Please see this link, you may learn something: Depth of field - Wikipedia, the free encyclopedia

Or search the internet for yourself to learn what DOF actually is and how it changes from wide angle to really small with super telephoto like a 1000mm
06-22-2010, 11:56 AM   #718
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QuoteOriginally posted by wildman Quote
Based on my experience I don't see any significant difference in DOF if FL length is the only factor and the subject is at the same apparent distance.

Case in point;
Two shots one taken very close up (about a foot?) with a FA35mm and the other taken with my 560mm, plus extension to bring the focus closer, at about 15 feet or so. Both about the same size on the same bush. The only difference is FL and distance between the lens and the subject. However, and I don't know how much difference this makes, but the 35mm was at f5.6 while the scope has a fixed wide open aperture of f7.
I've looked at the formulae for depth of field, and for a given circle of confusion, your hypothesis is practical. Image size is almost directly related to focal length over quite large ratios.

The standard DOF formula commonly used states that depth of field is related to the aperture, subject distance, focal length and the desired apparent circle of confusion. The formula is be shown as

where t is the total depth of focus, N is the lens aperture c is the circle of confusion, v is the image distance, and f is the lens focal length. The magnification of the image varies with v/f, and that indicates that for a given subject magnification, v/f is identical for both lenses, the 35 mm and the 560 mm, and the depth of field is identical in both cases. Going from 35mm to 560mm gives a relative change in focal length of about 16.5X, so you would need to be 16.5 times farther to obtain the same approximate image size, reducing the final term in the formula to the same value.
QuoteQuote:
As matter of fact I have a Sigma 105mm macro but find the 560mm is better on butterflies than the 105mm because I can track their abrupt random movement better on the scope with the gun sight mounted on it. After all for any given lateral movement of the subject the angular movement is much smaller on the scope at 15 feet than on the 105mm at 12 inches.
My M 400/5.6 has a "gunsight" on it as well. It is a really simple but effective way to find the bird in the viewfinder.
QuoteQuote:
Anyway take a look at these pics. Darned if I can see any significant difference in DOF between the two given the huge difference in FL.

If anyone else has any other theories about this I'm willing to listen.
06-23-2010, 06:27 PM - 1 Like   #719
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Might I present a shot of the rare genus, Sillyfurryious Pennykittyious captured easily here in her natural habitat (near the food bowl waiting patiently for her dindins)

Takumar 300mm F4 preset @ F8 + cheapo extension tubes and bounce flash

06-23-2010, 07:33 PM   #720
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QuoteOriginally posted by FruitLooPs Quote
Might I present a shot of the rare genus, Sillyfurryious Pennykittyious captured easily here in her natural habitat (near the food bowl waiting patiently for her dindins)

Takumar 300mm F4 preset @ F8 + cheapo extension tubes and bounce flash
Well done! She is patient to wait for that rig to work.
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