Jupiter 30/01/2013 HELP PLEASE

[long_arms]

Hello,

So last night I went out there with my normal set up however with an updated diy extension tube (its massive a good 5 inches).

The good news was the extension tube worked a treat. With my only barlow being the stock skywatcher 2x barlow Jupiter looked big on the screen but still focused sharp.

However, the dust/muck/who knows what on the sensor was ridiculous!

I have been noticing it for the past few weeks however with jupiter being smaller on the screen I havent been phased by it. I obviously only see the dirt where jupiter is placed, so moving jupiter around the sensor showed the full extent.

Now I brought it in, unscrewed the adapter and carefully gave it a blow with compressed air. I also did the same with the barlow. Went back outside and it was exactly the same.

I mean EXACTLY the same, moving jupiter around the dots/clumps were in exactly the same place. With the barlow removed I racked the focus right out to see mirror/secondary vanes etc and apart from the clear bad collimation I also saw all the marks allbeit less obvious. So I'm sure its on the camera.

Now I know people will say use a hurricane blower etc but surely if compressed air didnt move anything in the slightest a hurricane blower isnt going to help?

Stupid question maybe but these marks wouldnt be from either telescope mirrors? The extension tube reeeally increased magnification.

Should I get the sensor cleaned? The camera isnt expensive but I dont want to have to buy another one everytime this happens.

Heres a screenshot of what I mean (THIS IS THE BEST BIT the rest was a LOT more substantial.)

Here's the finished stack, quite reasonable aha!!

Please any help??

Dan

[Freddie]

Rotate the cam and if they stay in the same place on screen, they are on the cam. If not, they are on the barlow. If on the cam and the blower will not shift them, there is a cover on the sensor, so a light touch with a baader cloth or similar should shift them. Do all you can with the blower first though.

[andrewluck]

Pec pad and Eclipse fluid?

e.g. http://www.photosol.com/store/pc/home.asp

Andrew

[KevG]

I use a mini lens pen (similar to this), great for keeping the sensor clean.

[SnakeyJ]

Hi Dan,

did you confirm if this was barlow or camera (rotate barlow or camera)? if its is the camera you can open the cover, unscrew the lens mount from the board to gain access to the pcb and sensor directly - blowings all ways best, but I'd be a little cautious with compressed air - otherwise KevG and AndrewLuck's tips are worth a go with some caution.

I've see some people complain that some nosepieces drop flakes of paint from the screw threads, so best check this out before reassembling. Once you've got it together clean I'd suggest leaving a clear filter or UV/IR cut filter screwed into the nosepiece - not sure of the best source for a cheap/sacrificial one, but sure someone here will know.

best of luck - Jake

BTW - Your Jupiter is much better than mine turned out, too windy and the seeing deteriated very quickly for me after about 08:30hrs - hoping for another crack tonight or tomorrow, but weather looking iffy ;(

[long_arms]

Hello everyone,

Yes I have confirmed that it is the camera, (I rotated the camera and it stayed in the same place)...just tilting the sensor under light I can see a some.

So my question is,

I have numerous glasses cloths and similar, is there some sort of protection in front of the sensor!? There is obviously no ir filter or anything but could I use a blower on it, and perhaps a wipe with a cloth also?

To be honest it really cannot get any worse now, back when I posted this I would class it as clean compared to now.

Yes Jake I certainly need a filter to go infront! This has shown me how much so. As I have always been very careful, immediately after using it I have either put a cap on the end or screwed in the lens that came with it.

Dan

[Freddie]

Blower first and if that doesn't shift it, a specialist lens cloth. That's how I clean my DxKs.

[Bizibilder]

Take some flat frames. You will need an even white light source over the end of the scope - you can make a light box for under £10 - and run off a 500 frame avi every time you image or change the set-up during a session eg swap Barlow or refocus. The stacking software (Registax or Autostakkert) will make a master flat for you and subtract it from your images. Thus the dust will dissapear before your very eyes!

[Freddie]

Probably a lot easier just to clean it !

[SnakeyJ]

Dan - can u take it apart and get a close up photo of the cmos? Might help id the source of the debris. Could well be paint flakes from nosepiece threads.

[SnakeyJ]

Dan

Just opened my firefly up to take a look - very easy to with just 6 cross point screws;4 on case and 2 holding lens housing. The cmos does indeed have a glass cover so I reckon pretty safe to clean with usual respect for optics. Will add image in a bit.

Not the greatest but gives the idea!

Jake

[long_arms]

Haha bizibilder I was tempted to try a flat frame but it really is dirty now Seriously need to have a look at the diy section and find out how to make a light box on the cheap though, be much better than holding a laptop over the end!

Jake youre a legend! I will take everyones advice. I'll use a simple air blower and perhaps a careful wipe with a glasses cloth. At least I know it can't do any harm now anyway!!

There is 2 large bits which could certainly be paint! There is also a very even covering of small dots (like in my original post). Once I have a filter I certainly will not be persistently unscrewing the nosepiece.

Dan

[ilove1995]

Interesting topic. Dan, as you know I have the same webcam as you and the same problem with the sensor getting dirty. It's so bad now I've stopped using the firefly and use only the spc900 now. I'm going to follow Jake's advice and will take it apart for a good clean. Once cleaned I will keep an IR/UV filter on it at all times like I do with the Philips.

Al

[long_arms]

Yeh, I've got an Infrared pass filter coming either tomorrow or Thursday so will be cleaning it then. The filter will definitely be staying on!

Hope we both clean them successfully

I would love to have an spc900 to have used on planets! But for my lunar 100 and mosaic stuff the firefly is the way to go, so cant wait to get it cleaned now!

Dan

[ilove1995]

Would you mind sending the link for the filter your purchasing Dan. The only one I have is on the Philips and that one is staying where it is.

I love my spc900 for planets but like you I prefer using the firefly on the moon.

Al

[long_arms]

This is the filter I have coming. http://www.365astronomy.com/astronomik-proplanet-742-ir-pass-photo-filter-125inch-p-2186.html

Jake has one also, looking forward to seeing the difference it makes. I'll be testing it out on thursday so will post about it on friday. (I actually got it from modern astronomy but couldnt link straight to the filter).

An infrared blocking filter is pretty essential for a colour camera I've heard...but for a mono, with a bright object like the moon, an infrared pass apparently helps with effects of seeing and seems to give a much nicer image. I'll find out I guess.

Dan

[ilove1995]

Thanks Dan. Will be interested to hear how you get on once you receive the filter.

[JamesF]

I had a similar problem with one of my SPC900s. A blower wouldn't shift it so I resorted to a Baader cloth. Still took ages to get rid of everything though. I ended up doing some cleaning, firing up SharpCap with the camera plugged in and then moving the sensor across objects with different colours and lighting levels to see if I could find any more dust, repeating the entire process when I did. Some of the dust was quite reluctant to shift.

James

[long_arms]

Yeh I have found it really difficult to see the dust. The camera came with a lens but I have rarely got it in the right focus/ pointing at the right thing to actually see the stuff. In the scope with the lens off, its horrendous.

I'm certainly going to try pointing it at different colours thanks for the idea! I will try and get some images as well, so the stuff can be ID'd.

I think the large bits are either paint or foam (I have foam surrounding the adapter not sure how it would get in but still). The small bits are probably dust but it will be interesting to see. The fact that I can clearly see it with the naked eye on sucha small chip shows the extent.

The cloth I use for eyepieces etc came to clean the glasses for the TV. Seems identical to spectacles cloths. Light blue, silky smooth. Think it will be okay for this?

Dan

[long_arms]

Going to give it a clean in a bit, does anyone think I should lubricate the nosepiece (normal spc900 one) before screwing it in?

If yes household item recommendation please? Vaseline? I know nothing just thinking aloud aha

Dan

[JamesF]

does anyone think I should lubricate the nosepiece (normal spc900 one) before screwing it in?

I have never done so.

James

[long_arms]

I have never done so.

Thanks, just thought I'd check

[SnakeyJ]

Dan, I would think a very light smear of lube isn't a bad idea, might to reduce further damage on fitting/removing, help to hold on to any small particles of paint/plastic and at least it helps prevent corrosion of the aluminium nosepiece. Can't see any obvious drawbacks, though perhaps a wipe round after its all done up to remove any excess.

[long_arms]

I've just done a little clean, there was 2 large pieces which came away easily with a blower thank goodness. With a magnifying glass it looked like it could have potentially been a small bit of foam.

I've just plugged it in with the microlens in to check it still works, cant tell if its any cleaner atm. Very difficult to see the dust even when it was filthy.

Anyway, I know it works so no harm done at least.

Dan

[JamesF]

I found it easier to check without the lens, so the illumination on the sensor is much "flatter".

James