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Vignetting with Ext Tubes (1 Viewer)

Musoman

PETE - Nikon/Sony Shooter
United Kingdom
I decided to cut down the length of the engineerd alloy tube i used on my previous scope, because its a bit awkward to use

So with that cut down, i need to use an extension tube for close focus, so tried out both my AF chipped set, and a non chipped tube

The AF set with contacts is pretty useless when using all 3 tubes, because the slack is terrible. I can move everything so decided to only use the 36mm tube

I got vignetting with this AF chipped 36mm tube

I then decided to swop this for the manual / non chipped Jessops 31mm single tube.

I got vignetting with this too.

I know it doesnt matter too much in the great scheme of things, since all photos will be cropped down, but i was surprised at the vignetting.

I've now bought some of the cheap threaded type, just to check if these vignet as well. I wont know for a while as they're being posted from Hong Kong ( £4 ...very cheap ! ! )

On another issue, i notice that i need - 1EV to compensate for the over exposure. - 1EV seems to be about right after some experimentation
 

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On another issue, i notice that i need - 1EV to compensate for the over exposure. - 1EV seems to be about right after some experimentation

Interesting... -1EV is same value I had to apply when photographing with the E5 (4/3 DSLR).
 
Is that vignetting on one of the cameras listed in your signature? Big sensor on that 610 so I guess that would be prone to vignetting. Not noticed any vignetting on my D3300. I got some unchipped tubes which look similar to your Jessops one and they work ok, no difference in photos with or without them.

Paul.
 
Yes, the vignetting is on the D610, full frame. That would explain things!

I use the D610 instead of the D300 because the D300 has poor high ISO noise. ISO 400 is about as high as i would go on the crop body, but sometimes i want to shoot at 800 or 1600, and the D610 is much better for that.

I'd prefer a better crop camera for birding, a D5500 or D500 would be nice
 
The D5500 has the same sensor and processor as my D3300 and the low noise performance is very good. I'm happy to use ISO1600 and even up to 6400 is good enough for posting here.

Paul.
 
Yes i agree .. i think they both use the Expeed 4

Would be nice to own either but i blew my stash on the scope, so i'm stuck with a vignetting D610, but which has great IQ and high ISO quality, or swap to the APS-C body and take a slight hit on the IQ and poor ISO noise control

I 'll stick with the D610, since every shot is cropped down anyways, the vignetting is no big deal. Plus i've got those el cheapo threaded ext. tubes coming from HK soon, and maybe they'll help
 
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