anybody know what may be causing this?

Bolerus

Bolerus

Bolerus

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Strangely it doesent seem to show up on every monitor. But

Last week I bought a Tamron SP 500mm mirror lens, knowing full well what Mirror lenses are but wanted to play with 500mm (or 1000mm with the 2x convertor)

couple of days ago I went out and took the fololowing shot. there has been no PP to it at all, other than a basic crop to get it to a web page usuable size.

here is the pic

newmoon.jpg


/edit oops hit enter on title and it posted too soon


on some monitors (btu not the one im on now) I am seeing white pixels off the moon to the top right.

It was a cloudy night, is this some kind of digital image problem, or is it a problem with the way the lens is seeing the contrast between moon and night sky, or even a bad reflection off the mirror. or maybe some kind of polution?

If anybody knows I woudl be gratefull, just so I know and can be prepared for it.

I did ask this over on TP but i popped it on the end of a thread and I think that may have been a mistake lol (dont like opening new threads if i can just find one that fits - and the original thread was my own, asking for advice on which mirror lens to get )

thanks
 
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yeah maybe, funny that I looked at it on 2 monitors yesterday and saw it, but not there now. even just double checked it was the right image lol
 
If any of you own monitor calibrater's and can't see the problem suggest you take them back to where you bought them and get a refund :P

I see the spots (it actually looks more like an under saturated/under exposed light gray cast) starting at 11 o'clock on the moon and going round to 6 o'clock, it's significantly more 'spotty' at the top right of the moon.

It looks a lot like flare to me, I can only assume that it looks as strange as it does because it's a mirror lens.
 
un-calibrated, bogo cibox screen here and i can see them. anyone that cant, run the colour dropper over them in photoshop and you'll see.

not sure why they're there though, glare, atmospheric noise? i dunno
 
Nothing here :)

// EDIT // Well really squinting at it, maybe there's a slight halo, but the place I noticed it first was off the bottom right.

That isn't hard to get rid of in PS.
 
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There are grey areas at the top half and bottom right (although to a lesser extent), viewing on a calibrated PVA based screen ;)
 
glad you can see it, the 2 monitors i could see it on were both calibrated, so that sorts that problem out lol.

I know it is very easy to fix in PP, but I wanted to know what it was, so I know how to combat it in the field so to speak.

to be honest, it wasnt on every shot, and considering its a mirror lens, im quite happy (but I havent had a go at any wildlife etc yet)
 
On a much better monitor now (though not calibrated) and I can see what you are getting at, but still, in pchop for me there are no "white" pixels in that image.

I can see some luminance below a threshold of about 24, which just looks like a the shine off the moon. You can only see them because the image is enlarged so much. This is not an lens issue, it's a digital image issue.
 
ocuk_17930825_newmoon.jpg

Shadow highlighted in Photoshop (CTRL+H) to emphasise what you mean:

It is visible to me in your OP though too.

I think you'd see this disappear if you shoot at iso100 and shoot in RAW instead of JPEG. Give it a shot (!)
 
Can see them on my calibrated iMac. My guess would be that it is reflected light of the moon that has become very noisy and instead of appearing as a glow around the moon came out as speckles from an paint can. Or the moon is turning to dust!!
 
Didn't see any spots on my 3 work monitors (one is calibrated) other two on default settings. I do see the grainy lighter glow on the top right corner though.
 
As I suggested, shoot RAW, shoot iso100 (not 400 as you have done), problem solved.
 
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