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Are these dust bunnies?

PostPosted: Thu Dec 29, 2005 9:42 pm
by johnd
I'm having trouble with what I think are dust bunnies.
I first noticed them with my Sigma 150mm macro lens when focussing at minimum distance of about 35cm.
The strange thing is that they aren't anywhere near as noticable when focussing further out with the same lens or with any other lens.
I'm not saying they're not there with other lenses, but if they are they're hard to see and if anything, they're just a regular blurry bunnie not sharp like these.
Is there something about a macro lens focussed up close that would make any bunnies stand out sharply like these?
Please see the sample below with the :?: bunnies :?: pointed to by arrows.

Image

I've given the sensor a good workout with a giotto rocket but can't shift them.
I've never done a wet clean and am a bit reluctant to go down that path without having someone show me.
It's a bit far to get to a mini meet at Birdy's and none of the other photogs I know have done a wet clean.

I know there's some good advice on the forum about wet cleaning the sesnor, but before I start I thought I'd ask opinions.
Dust or not :?:

Thanks in advance, John

PostPosted: Thu Dec 29, 2005 9:53 pm
by frink
Almost certainly dust. They tend to show up more at smaller apertures. I don't have a dedicated macro lens but I certainly notice them more when using extension tubes for macros (even if the aperture is fairly large).

Stop any of your lenses down to smallest aperture, shoot a white wall or blue sky, perform auto levels on the image and prepare to be horrified :lol:

PostPosted: Thu Dec 29, 2005 9:58 pm
by Alex
John,

Look like dust on the sensor/ filter. To confirm, use a different lens at minimal aperture, e.g. f22 (kit lens) and shoot a blank - best clear sky or a white sheet of paper, then view image at 100 % (running auto levels in PS) helps seeing sometimes. If they are still there then they are on the sensor. You may need a wet clean. I only had to do mine once about 10 month ago, giotto did the rest. But the wet clean is a breathe although really nerve wrecking when doing it for the first time. I bought a kit from http://www.copperhillimages.com almost a year ago and it is great. Let me know how your test goes and if you need some advice on wet cleaning.

Alex

PostPosted: Thu Dec 29, 2005 10:29 pm
by johnd
Stephen and Alex, thanks for your advice. When using my macro lens, I'm invariably shooting at f22 (minimum aperture). This shot was certainly taken at f22. I'll try all my lenses at minimum stop against a white wall, auto level in PS and see what I see. I think, as you suggest, I'll be horrified. :(

Cheers, John

PostPosted: Thu Dec 29, 2005 10:42 pm
by frink
If those are the only spots you can see at f/22.. I think you're doing pretty well, your sensor is much cleaner than mine.. :)

It's virtually impossible to keep it clean for very long and you're gonna see dust much sooner at small apertures, fact of life with DSLR's i'm afraid. The heal brush in photoshop certainly gets a workout with me sometimes.. :P

This was mine before I gave it a blow a few months back, and that's only at f/8
Was also after I had been using the lensbaby a bit which kinda acts like a pump as I found out.. :oops:

I wouldn't fret too much though, take your time, read instructions carefully, get someone to walk you through a wet clean if you're not very confident and you should have a nice clean sensor in no time :wink:

PostPosted: Thu Dec 29, 2005 11:46 pm
by Matt. K
John D
Your problems are not dust bunnies....they are large red arrows that seem to be imposing themselves on your images.....Get yourself a copy of Nortons red-arrow remover.....

PostPosted: Fri Dec 30, 2005 7:42 am
by mudder
G'day John,

The wet clean method isn't that scary with the benefit of hindsight, but it's daunting the first time (I know I was very bloody nervous when I did mine!), just don't expect to get it perfectly clean and try heaps of times, the little buggers will be back soon enough, just keep 'em under control and like me get the hang of the healing brush :lol:

I had mine basically spotless after a wet clean using heaps of sensor swabs, but within a few weeks was noticing a couple of newies, so I'd probably only do it when they become a problem, the ones that look like little hairs would be trickier to cover up in PP than the "spotty" ones... (like Frinks! Strewth yours was grubby :lol: )

Cheers.

PostPosted: Fri Dec 30, 2005 7:51 am
by radar
Hi John,

As Matt as mentioned, that red arrow remover will work a treat :twisted: :twisted:

I did my first wet clean before Christmas following the Copper Hill instructions. I had a number of very persistent dust bunnies that the air rocket would not dislodge. I've had my D70s for about 6 months now.

Got some pecpads and pure methanol from Birddog and a spatula from Copper Hill. I wasn't game enough to make my own. Had about 10 bunnies prior to starting, after the first clean, down to one. Did another pass, clean sensor :) :)

You can get a whole kit that has all you need from Quality cameras, see it at:
http://www.qualitycamera.com.au/

Stu if very helpful on there and good service. They are the authorised Oz reseller of the kit. The full kit with pecpad, eclipse fluid(essentially methanol), spatula, etc sells for $63. Even comes with a printed instruction booklet. Just add a stiff drink, before or after clean, and you are fine :wink: :wink:

HTH,

radar

PostPosted: Fri Dec 30, 2005 8:16 am
by Nikon boy
Hi John, living with digital camera's initially had me very concerned about the dust problem as i was working in newspapers at the time and was told by the press photographers how they had big dust problems, so when i went digital over twelve months ago i was a little paranoid, i did however decide to attempt to keep everything as clean as possible,
i get dust bunnies i reckon everyone does , but i have never had to do a wet clean in the time i have beenshooting, and this includes weeks in the dusty outback changing lenses all the time,
My method is i clean fronts and backs of my lenses before and after each shoot, i also blow out the sensor and the mirror box before and after as well, added to this during a shoot if i am changing lenses a lot i will blow out the sensor as well, in short i clean everything very often, i never give the dust a chance to become permanantly attached to anything, this has become a part of my photography just like turning the camera on, i do it all the time,

Just my two bobs worth

PostPosted: Fri Dec 30, 2005 8:57 am
by johnd
Thanks for all the advice everyone. I posted a bee shot last night. It was taken with minimum aperture and had about 5 or 6 bad spots, but healing brush took them all out in less than a minute.

Matt and Radar, I've worked out how to turn off the "Point at spots with red arrow" feature now, so shouldn't be plagued with that any more.

Cheers, John