Search found 595 matches

by PaulFurman
Sun Oct 02, 2011 4:44 pm
Forum: Nature Photography -- Macro and Close-up
Topic: Orbweaver
Replies: 0
Views: 604

Orbweaver

Hey, long time no see, I've been on other tracks but did a few stacks yesterday and thought I'd share: Orbweaver Spider on Gum Plant Pier 94 Salt Marsh, San Francisco -handheld focus stacks of a few shots each. -85mm f/2.8 PC Micro with extension tube -ISO 800 1/300ish f/13ish overcast skies https:/...
by PaulFurman
Mon Jul 18, 2011 11:07 am
Forum: Technical and Studio Photography -- Macro and Close-up
Topic: Crane fly-Típula-Tipulidae (56 pictures stack)
Replies: 10
Views: 1848

LED's, even white ones produce discrete spectra. I suspect you're thinking of LED arrays in which RGB light gets produced in a single step, straight from the semiconductors. However, typical "white" LED's use a two-step process involving phosphors, which fill in the spectrum pretty well. You're lef...
by PaulFurman
Fri Feb 25, 2011 6:31 pm
Forum: Macro and Micro Technique and Technical Discussions
Topic: DOF and Sensor Size
Replies: 20
Views: 7058

The Nikon Multiphot was designed for large-ish format macro work.

Bjørn Rørslett's page:
Macro-Nikkors are excellent performers and within their specified magnification range will cover up to 4x5" format with ease.

BTW, Thank you Rik for commenting! :D
by PaulFurman
Mon Feb 21, 2011 11:27 pm
Forum: Macro and Micro Technique and Technical Discussions
Topic: DOF and Sensor Size
Replies: 20
Views: 7058

DOF and Sensor Size

Here's an interesting discussion on alt.photography: Re: DOF and Sensor Size The premise by my reckoning is that smaller sensors actually have an advantage for macro because they are not working in the macro realm as soon as a larger sensor (where effective aperture can limit things due to diffracti...
by PaulFurman
Fri Dec 31, 2010 1:18 pm
Forum: Nature Photography -- Macro and Close-up
Topic: Leaf cutter ant video (not mine)
Replies: 1
Views: 547

Leaf cutter ant video (not mine)

Some pretty impressive video of leaf-cutter ants cutting leaves:
http://www.sciencefriday.com/program/archives/201012312
-not mine!
-the last 2/3 is actual footage
by PaulFurman
Sun Dec 19, 2010 4:39 pm
Forum: Technical and Studio Photography -- Macro and Close-up
Topic: Assorted flower stacks
Replies: 10
Views: 1798

Well done John, these are difficult subjects. How many frames? Stopped down a lot?
by PaulFurman
Tue Nov 09, 2010 6:35 pm
Forum: Equipment Exchange
Topic: Looking for Voightlander 125mm f/2 for Nikon.
Replies: 13
Views: 5634

I got one with a pentax screw mount which adapts somewhat usably to Nikon for focus up to about 15 feet away I think. The price for Nikon mount version is disproportional. The aperture control pin needs to be glued in and the square lens shade doesn't align (if anyone wants that shade, I've got one)...
by PaulFurman
Mon Nov 08, 2010 7:33 pm
Forum: Nature Photography -- Macro and Close-up
Topic: Robber Fly (Cerotainia sp) and prey
Replies: 10
Views: 1559

Oops, sorry, it was Assasin Bugs, not Robber Flies: http://news.discovery.com/animals/assas ... iders.html
by PaulFurman
Mon Nov 08, 2010 6:52 pm
Forum: Nature Photography -- Macro and Close-up
Topic: Robber Fly (Cerotainia sp) and prey
Replies: 10
Views: 1559

Ouch, that's a big parasite in the video. Nice stills too.

I read something recently about how these robber flies catch spiders by reaching out to the web and cleverly simulating the vibrations of a struggling prey. They measured and tested various vibrations and the fly had it exactly right.
by PaulFurman
Mon Nov 08, 2010 6:34 pm
Forum: Administrator's Appreciation Gallery...Photography Through the Microscope
Topic: Spiders No.15 - Pholcus phalangioides Hatchlings.
Replies: 8
Views: 6324

Wow, congratulations for the 'huddle' shots, and such careful persistence on this project!
by PaulFurman
Sun Nov 07, 2010 5:23 pm
Forum: Equipment Discussions
Topic: Unusual Lens (not necessarily a macro lens)
Replies: 12
Views: 3970

Craig, I can use a macro lens to focus on the virtual image and get it to fill the FX frame that way, or I can put a 1.4x teleconverter on but that effectively stops it down, and appears to increase DOF, which sort of loses interestingness. I did try various other lenses as shown in your link withou...
by PaulFurman
Sun Nov 07, 2010 12:26 pm
Forum: Equipment Discussions
Topic: Unusual Lens (not necessarily a macro lens)
Replies: 12
Views: 3970

Harold, what is the back focus for that lens? If it's for 35mm slides, it will cover a 35mm sensor but might not focus to infinity. I got started on this looking at movie theater projection lenses, which are supposed to work on DSLRs, old ones with about 100mm f/1.8 specs seem to go for $50 +- The k...
by PaulFurman
Sat Nov 06, 2010 3:21 pm
Forum: Equipment Discussions
Topic: Unusual Lens (not necessarily a macro lens)
Replies: 12
Views: 3970

Humm, not bad Paul---beautiful bokeh! Does it appear to be symetrical, PMF=1? Far from symmetrical; from the rear, the pupil appears to be 1-3/4 inches wide, looking into the front it looks about 1/4 inch diameter, so that's a pmf of 0.14? I always mess up the math though! Does that mean at 5x, it ...
by PaulFurman
Sat Nov 06, 2010 12:23 pm
Forum: Equipment Discussions
Topic: Unusual Lens (not necessarily a macro lens)
Replies: 12
Views: 3970

Bob, Well, it does sort of work reversed, I just reversed the two-tripod arrangement shown: http://www.photomacrography.net/forum/userpix/790_DSC_5225_1.jpg That has about three inches between the lens and subject with the camera almost touching the front element and some black material draped over ...