What is wrong with me?!

Marc-Etienne · Apr 6, 2011

Seriously, I'm glad that my fiancé is understanding... I came out of the shower yesterday and that little guy was cruising down the steamed wall. I only did insect macro once (got my lens beggining of winter :er

and wanted to take that opportunity! I ran out in boxer to get my camera gear and gave it a go. I wish I had my ring flash... but with the level of preparation, I decently happy!

All three shoot with a Nikon D90, a sigma 105mm macro, ceiling bounced flash, at f14, 1/200s and ISO 200.

I noticed that without my ring flash, I often have a greenish glare relatively centered when the lens is stopped down below f/10ish, it annoyes me a little bit, but didn't have the ring flash handy :grumpy:

#1

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#3

Thanks for looking, commenting, critiquing or giving inputs

TheFantasticG · Apr 6, 2011

Very interesting on the green spot. I have that problem with my iPhone under a florescent only light source.

Does your flash use FP?

Marc-Etienne · Apr 7, 2011

Thanks for answering FantasticG!
From what I read, my flash might be able, but this time, it was on single burst manual 1/4 or 1/8 of power. My flash does stroboscopic, but I never thought I could use it for highspeed photography. I think the greenish spot is a consequence of the direction of the light and the aperture. Like I said, I don't have any problem with my ring flash, but with ceiling bounced or side mini-softbox, I get that spot. Below you can see of the test I've made to try to figure this out. I shot a with sheet of paper at varying aperture. Lighting is a 1 ft X 1 ft mini softbox perpendicular to the lens (camera right) about 2 ft away. I can't remember the flash power output, i did that at Christmas

f/2.8 - Fine

f/3.5 - Fine

f/4 - Fine

f/5 - Fine

f/8 - Subtle green spot

f/9 - Obvious green spot

f/10 - Obvious green spot

Could the lens have glare issue only at certain aperture?

TheFantasticG · Apr 7, 2011

That, I don't know.

The D90 FP syncs upto 1/250. I use 1/320 on my D7000.

Davor · Apr 7, 2011

The D90 syncs up to 1/4000 with flashes that support creative lighting systems.

Are you using any kind of filter on your macro lens?

Marc-Etienne · Apr 7, 2011

I don't really own the most fancy flash (Quantaray PZ-1 DSZ). It is a tank, if I ever get attack, I know what I'll be going for!! Not sure if my flash max speed is 1/200, but I can't get any faster, the camera doesn't let me. Thanks for your input FantasticG, I'll try the strobe option see if I can get faster shutter speed. It won't fix my problem, but might be handy to know!

Davor, I have a stepping ring to screw my 72mm CPL, but those were bare lens. Thanks for trying to help!

TheFantasticG · Apr 7, 2011

Davor said:
The D90 syncs up to 1/4000 with flashes that support creative lighting systems.

Even so, there's so little light getting to the sensor from the speedlight when you're over 1/250 @ F16 (and higher), there's not much point in going higher on the shutter speed after that, at least at ISO 200, if you're only using one SB-600. At least, that's what I have found on the D90. It got marginally better when I added the R1 kit, but I still never had enough light using TTL-BL-FP above 1/320. And using TTL-BL, it just blasted too much light at any given shutter speed. On the D7000, I'm still using AUTO FP, just on 1/320 now when I can, otherwise I fall back to 1/250 @ F11 and higher, @ ISO 100.

Stephen.C · Apr 7, 2011

Good captures, although I find the background a little distracting. Wouldn't mind a little bit of a closer crop.

Derrel · Apr 7, 2011

A centrally-located "dot" of flare has been noted before with digital cameras. "Some" lenses and "some" cameras have a pretty serious issue; the Kodak 14n SLR had a red dot issue with a number of lenses, like the Nikkor 50mm f/1.8 AF-D, Tamron 90MM AF-SP, and other lenses; the issue was quite widely discussed a few years ago under the term "red dot syndrome". The issue is one of the lens's diaphragm and the sensor's anti-aliasing array causing reflections. Your ring flash could easily be the problem.

Marc-Etienne · Apr 7, 2011

Thanks Stephen for the input!

Thanks for the info Derrel, I'll look it up. The ring flash seems to solve the issue actually. The spiders above are ceiling bounced lit, the white sheet of paper are softbox lit perpendicular to the lens and the following picture is ring flash at f/14 like the spider. The green spot is gone...:scratch: I'll try to remember not to forget the ring flash next time I shoot macro. I just wish there was something to do...