Dam

14 hours ago, ONIKKINEN said:

The proper tool for the job of opening the retaining ring would be a lens spanner:

You can also use circlip pliers or needle nose pliers, but that can be finnicky depending on how tight the retaining ring was tightened and im guessing the previous owner used something like that and had some trouble judging from the scuffs. If the marks are on the glass filter only and are not actual scratches but some kind of dirt then i guess you could just try to clean it with some isopropyl alcohol and something that doesn't have a risk of scratching the glass, like some cotton wool. You should do this in as dust free of an environment as possible and have something nearby to immediately cover the sensor once you remove the glass. And check that what you cover the sensor with is not dusty itself actually. If you're lucky you wont get dust inside the sensor, but household dust suspended in air can easily make its way onto the sensor.

I dont know how this particular camera is built, but if it has desiccant tabs integrated somewhere inside the glass window (like mine), you could also accidentally saturate those if you have high humidity indoors and have a risk of dew forming on the sensor later. That is part of the reason why certain camera manufacturers dont want people poking inside.

Thank you for sharing this information i dont think i will ever take one apart as i am not qualified to do so but it is good to know there is dedicated tool for that task. However even if it is only glass damage i will need to find a dedicated near by astronomy place shop to do it for me or the camera place (providing they can do that in safe environment). Thank you. 

13 hours ago, tomato said:

This advice is obviously way after the horse has bolted, but if buying used Astro kit without inspecting the items in person, always request up to date photos of the critical items, e.g. lens, mirrors of telescopes and sensors of cameras. It’s not a cast iron guarantee but it will give you some assurance that the equipment is OK. If the seller won’t provide these, I would decline the sale.

Yes thank you very much and i shouldn't have known that but sort of trusted thr sellr according to their reviews on ebay and the fact that it was good deal i should have be more suspicious but lesson learned. I am only hoping that it is a glass damage rather then sensor but will try and get more pictures at different angle to see if it shows up. Thank you very much. 

13 minutes ago, Clarkey said:

At least if it is the glass you might be able to replace it. If it was the sensor - no chance.

Just checked the Altair website. It looks like they sell the glass windows as stock - you might be in luck.

Thank you, you are true gent thanks for checking that for us. I just need to confirm somehow that it is not sensor but the filter galss and too scared to take it off in case dust goes in 

2 minutes ago, ONIKKINEN said:

Above all else i would try to return the camera to the person you bought it from. If they have any shame they would agree to cancel the deal, but i wouldn't hold my breath on that. I dont know about UK laws so cant advice on that but i think this can be interpreted as a fraudulent sale from the looks of things. The previous owner has obviously opened the camera and done that using tools not fit for the purpose (the marks on the ring) so this paints a picture of a complete nonce doing something to electronics with no experience on the matter at all. After doing whatever they did to the camera they left some crud possibly on the sensor itself (hard to tell from the image where the mark is, the sensor, the sensor window inside or the outside), which is very difficult to clean. Basically if you dont have a clean room you will get a dust particle or two on the sensor.

You are very correct sir and it is an ebay sale so am.hoping am having some kind of cover via paypal but wouldn't hold my breath as seller did state no returns so will dispute it as not fit for purpose . However i wonder if i should attempt to take a ring out and inspect as it seem to be a IR clear filter from what i can tell  so hopefully there is no damage to sensor but dont want to expose sensor to dust.

4 minutes ago, Clarkey said:

Agreed. Looks like damage to the sensor - although difficult to tell from a photo. I think you would be entitled to ask the seller about it. 

Agree its hard to tell from pircture but having shined the light on it looks like its a mark on the actual glass / filter as it has a coating on. Email sent to seller just now. Will co tact altair see if they sell those as individual piece. 

2 minutes ago, ONIKKINEN said:

If you just bought the camera, stop before doing anything to it and return it to the seller. If bought used, good luck, but if bought from a retailer of any renown you will get a new one. From the looks of things it looks like someone has "improved" the camera and left their watermark to where it should not have been left.

Yes bought it as used unfortunately and am guessing am stuck with it now. Yes looks like it a very nice improvement 😄 overall. Wonder if this filter can be replaced with new one? Any thoughts? 

4 minutes ago, david_taurus83 said:

What camera is that? Looks like someone has already had a go at it by the look of that retaining ring..

Its Altair Hypercam 183C Pro. I had it recently purcahed (used) tho. 

Just a quick update i took my train apart and found this on camera glass😱?? Is this damaged  coating or just a dirt? Not sure if this is culprit but looks very bad.

3 minutes ago, Xilman said:

Check for an eyelash while you have the kit disassembled ...

Ahh will do indeed thanks for pointing out. 

21 minutes ago, tomato said:

@Clarkey has beat me to it, but those  intense dark shadows look like dust on the sensor cover of the camera. Flat frame calibration will usually remove dust motes but in my experience ones as prominent as these will cause problems in the final image even with flats. As already advised best to take the camera off and blow it clean with a dry and oil free compressed air source.

Indeed it is very intense area and cant really pinpoint where it is in imaging train. I have tried flats calibration but to no much succes it is still very much there not as dark put still prominenet. My cam is hypercam 183c pro and has this glass element filter screwed on top of sensor. Should i take it off and  lean it with microfiber  cloth or just blow the dust off? 

18 minutes ago, Clarkey said:

Looks like dirt in the image train. Different places I suspect and quite bad. You need to check the sensor and any glass / filters near the camera. Just be careful cleaning - ideally just blow dirt off with a puffer but you might need a small lens brush.

Thank you for your reply. Yes its very bad 😔 i could not see anything on the refractor lens but the normal dust particles  however did not check the camera sensor as am scared to touch the glass filter in case i damge coating. There is a flattener in a train which is brand new and got it out of box first time i took this image but will check it regardless. Thank you for advice 🙏  much appreciated. 

Hey all,
Hope everyone is ok. I need help please, does anyone know what those dark spots in my images are? Is this a dust or damaged coating on my refractor lens?
I am getting a dark smudge on all of my pictures. It's in the top left corner of the picture I have here.
Is this just dust on the sensor? Or perhaps something worse?
Thanks for any help you can provide.

p.s apologies in advance if posted in wrong thread wasnt sure where to post. 
Br,
Dam

Thank you.

On 12/06/2020 at 13:05, alacant said:

To correct any residual colour we used a #8 yellow.

 

I assume you are referring to a  #8 Yellow Filter ?

On 12/06/2020 at 13:00, ollypenrice said:

 (Keeping the F ratio low without colour fringing gets harder and harder as aperture increases.)

Olly

Many thanks Ollypenrice , that i didn't know  thanks for pointing that out.

On 12/06/2020 at 10:32, vlaiv said:

 

As for accessories, I don't think that you should worry about it now. Part of the fun (for me at least) is discovering what you need and anticipation and the thrill when you get new piece of kit and wait for a chance to test it out.

Here is something that you should consider, but like I said, it will depend on your interests / taste. I would consider 2" diagonal mirror if you don't already have one and wide field eyepiece. 6" refractor is very good scope for wide field viewing of Milky way and large open clusters.

If you are serious about astrophotography - consider getting autoguiding kit at some point. That means guide scope (you can turn your finder scope into a guide scope or add separate guide scope instead of finder scope) and planetary camera. Planetary cameras can be a lot of fun. You can take better images of the Moon and the Planets with them and even some Deep Sky imaging - that is how I started into AP.

 You can use Semi APO filter or even regular #8 Wratten yellow filter. Very good filter for that is also 495 long pass filter (from baader - it is deep yellow filter). Problem with yellow filters is that it will skew your color balance, but that can be corrected in processing phase

- Another thing that you can add is aperture mask. That is something that you can't purchase, but you can make one, even out of cardboard. With nowadays 3d printing - it is very easy to print one to suit your needs. Aperture mask is just a mask with smaller aperture than original aperture of telescope. Chromatic blur of achromat telescope depends on clear aperture size. Reducing this size removes some of chromatic blur.

Don't think that your scope won't be able to produce good images - it is just a bit more complicated and appropriate technique needs to be used. Here is example of what F/5 achromat (2 lens simple design with a lot of CA) can do with planetary type camera:

 

Hi Vlaiv, many thanks for the pointers much appreciated, note taken of all of them. Really appreciate time you taken to get this down. This indeed will help me to get on the right leg and start in right direction. One thing am sure it certainly is very expensive learning curve i would say but very rewarding too . I think i have a lot there to start with so hopefully get some clear skies soon  as it been constantly cloudy and rainy   . Once again, many thanks.

Hi Both, 

Thank you for the welcome and thank you for the prompt replies and advice. 

@Dave thanks for the link i have seen that on the FLO website but i wasn't sure if that was the correct for the telescope, thanks for clearing that up   

@Vlaiv thank you for welcome and many thanks for reply. Yes, it does have 4 lens actually and i also have got semi apo filter which i hope it will cancel some CA  😐  . I have taken a picture of the Moon other day and have noticed some faint blue around the Moon but i wasn't using filter and took image with my mobile phone thur eyepiece only. Could that be the reason maybe why (sorry i am not an expert and just trying to figure things out)? Visually i couldn't notice any CA. 

Would you guys recommend any other accessories / equipment that i might need to purchase   that will be needed in a long run?

Mnay thanks... 

Hi There Good People,

Hope everyone is well and safe. 

Not sure if this is correct place to post in since am newbie here and it is my first post so i hope it is ok.

I have a question or two that i need a help / advice with and i can't figure it out for the life of me which focal reducer/flattener will i need with my setup? I have recently bought Brassier AR152S/760 f/5 telescope with HEQ5Pro mount and few other accessories so i can do visual observing and at some point, do AP. However, was told that having a reducer/flattener in my optical train is a must have for AP and have since been browsing internet for more info on what is the correct focal reducer / flattener but i can't seem to figure out which one would work best with my refractor. I have Altair HyperCam 183c and some people suggested that i don’t need the flattener with my setup some people do and am confused now which one i would need lol. 

I hope that someone here can shed some help and advice and set things straight for me lol, i would appreciate that very much. 

Mnay thanks in advance and looking forward to repsonse. 

Best, 

Dam