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10-02-2020, 12:59 AM   #61
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QuoteOriginally posted by SpecialK Quote
I post this for giggles. It is a 4-element, 2-section, 800mm "tuber".

I bought it used and sold it for less.

New owner said it was sharper than his (unknown) mirror, and thanks.

Never really got above "fairly poor" images.
The bottom image has a very dreamy quality to it. Kinda reminds me of the Pentax 85mm soft focus lenses. It's nice but not in a great big 800mm lens. Portraiture is hard when you are a hundred meters away from your subject.

I recently acquired an SMC Pentax 1.7x AF Converter and was pleasantly surprised when it worked with my SMC Pentax A 400mm f/5.6 lens. You dial in the focus on the lens to "close enough" and the converter will then fine tune it to "spot-on." By way of contrast(!) a Tokina RMC 400mm f/5.6 does not work. The converter just hunts back and forth and then gives up.

The converter is a good option, but only the best glass will work with it. In other words, if it doesn't say SMC on the lens barrel you are on your own. Even then, a maximum aperture of f/8 or f/11 might not cut it. I don't have any other super telephoto lenses so I can't give any opinion.

My LBA side really wants an 800mm or 1000mm but my practical side wants to know what it will be used for. The 400mm lenses see little enough use as it is.

10-05-2020, 03:33 AM - 1 Like   #62
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QuoteOriginally posted by photoptimist Quote
Physics is a bitch. A 750 mm lens at f/8 requires at least a 95mm front element -- it's a lot of glass and that's not cheap.

A decent long telephoto always requires an indecent amount of money.
....and an indecently heavy tripod
10-06-2020, 09:12 AM   #63
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QuoteOriginally posted by Fenwoodian Quote
Wear camo, maybe even work from a blind. That will enable you to get closer to your subjects. From an IQ standpoint, I'll take the results from a 300mm - 400mm lens any day over a 750mm lens.

I've worked with a number of professional wildlife/bird photographers. None of them ever used a lens over 600mm. Most used EXPENSIVE (over $10,000) 400 and 500 lenses.

A quality bird image will have: every feather sharp enough to see the individual veins in it; catch light in the bird's eyes; colorful and tack-sharp eyes; AND the bird doing something extra-ordinary.

Last week I was shooting burrowing owls in Arizona USA with expert Canadian bird photographer Anthony Bucci. Check out his website, you'll learn much about bird photography.
Thanks so much for posting the info on Anthony Bucci. I read some of his blog posts and found them very informative, especially his story about becoming a wildlife photographer. That, in my opinion, is a must read for all aspiring wildlife photographers.
Post Page (

Did you get any owl photos? Please post them if you got any.

Last edited by onlineflyer; 10-06-2020 at 11:27 AM.
10-06-2020, 12:46 PM - 2 Likes   #64
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Every time this title comes up in my feed I start laughing. Affordable, 750mm+, with IQ needed for birding...

First defining affordable is always tricky. One man's "affordable" is another's "out of the question". I have relatives who think nothing of giving $50000 Christmas gifts to each other (Not a typo). I can't imagine that level of financial cash flow.

Suffice it to say, this thread gives me a laugh every time I see it float by.


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