Help with Mars photography

JohnH · #1 26-10-2005, 08:59 AM

Help. I have a fuzzy orange blob after my first attempt at mars photography last night. Shots were taken around midnight - I do not think the seeing was good - I used the ETX90, LPI and a 2x barlow. Gives a magnification of approx 400x which is the limit for this scope. Perhaps too much however I wanted some image scale.

I captured using Autostarsuite and have approx 800 images of varing quality however when I try to process these in Registax I cannot get any improvement except a little contrast, attached are a single shot and a stack of 400...

Help! What should I do first to improve my mars imaging?

rumples riot · #2 26-10-2005, 09:14 AM

The image looks reasonable, but you will find that without an IR-UV cut filter your images are going to be a little fuzzy. I can see some detail there, so that is a good start. Only use images that are sharp, try not to use blurry images.

Try using K3CCDtools to take avi's with the LPI. The program will recognise the LPI and I have used it in the past. Much better for this sort of thing.

If the image was jumping all over the place then seeing would be the problem.

Best of luck.

JohnH · #3 26-10-2005, 09:59 AM

I was hoping someone could clue me in - was seeing poor last night at about midnight - I think it was not great as rate at which I could collect "good" frames was slow...but I am not experianced enough to say for sure. Anyone else have a go at Mars last night from Sydney region?

When is it best to image mars at the moment (assuming it is clear!) my shots are from midnight to approx 1 am. Is a filter mandatory to get rid of the fuzz, if so which one should it be?

bird (Anthony Wesley) · #4 26-10-2005, 10:23 AM

John, assuming your scope is reasonably well aligned and collimated, seeing conditions and thermal equilibrium will make up 95% of your problems...you need to allow at least half an hour and maybe more ike an hour for your scope to sit outside before it will have reached thermal equilibrium with its surroundings and give you good results. I know it's only a 90mm scope, but I recall that those scopes are enclosed so the air inside the scope has to settle down as well.

The way to check is to try looking at a star first just with an eyepiece at high power. If the star is jumping around and looks fuzzy then you can forget about good planetary views :-(

In general, the longer you can leave your scope setup out in the evening air before you start imaging the better your results will be.

Mars is also very low in the north, even from Sydney, so you can expect real problems trying to get a good view, especially from somewhere like Sydney.

An an alternative you might try setting up the scope around midnight and having a go at Saturn at around 4am. It's a lot higher in the sky and at that time of the morning you should get a better quality image.

regards, Bird

Hitchhiker · #5 26-10-2005, 12:48 PM

John, I think that is a good image for a first attempt at Mars.

I had my first attempt at Mars last night, too. Used a DSI rather than LPI - haven't had time to process yet!

Did you use a tracking box in Autostar Suite? I only ask because in my initial imaging I did not draw a tracking box around Mars and the combined image was fuzzy. With the tracking box everything was a lot clearer.

Keep up the good work!

davidpretorius · #6 26-10-2005, 01:37 PM

Good one John,

i try and wait until 1 oclock when it is nice and high in the sky, also with my dob, i can then move my scope in one direction only to follow the planet.

THe last three nights have been lousy for seeing. I have been using a 12mm (100x) first and seeing if i can see detail. If i can't then there is not much trying the toucam for imaging

are you able to adjust the exposure and gain on the lpi.

asimov (John) · #7 26-10-2005, 02:56 PM

Hey, that's not a bad 1st image of mars really! Better than my 1st. In total agreeance with what the others have said. Good seeing is a must.

Hitchhiker · #8 26-10-2005, 08:55 PM

JohnH, here is my best effort from last night. First time imaging Mars for me too.

Shot with a 10" LX200 GPS with a 2x barlow.

As far as improving your imaging there are a couple of things I know I need to do - you may be in the same boat.

First - I focus by looking at the image on the laptop screen. To achieve better focus I am going to build a Hartmann mask (see Projects & DIY section). This lets you focus on a star before swinging over to Mars.

Second - Collimation. I think my collimation is pretty good but I know it can be a lot better. Practice makes perfect!

Last - Seeing - can't do too much about this except making sure you site your telescope at the best place. My images last night were taken looking over my garage roof. This roof is colorbond so it still radiates heat into the night. I suppose if the seeing is not good then I shouldn't bother imaging.

Good Luck!

JohnH · #9 26-10-2005, 09:43 PM

Thanks to all for your input - I think perhaps I cannot do much more with the little 90mm scope and LPI? I will try imaging later when Mars is higher, I cannot adjust collimation on the little MAK afaik however I do get airey discs on bright stars and nice round donut shapes either side of focus so I think it is ok....perhaps the IR blocking filter would assist a little however I will make a few more attempts before I go for a $$$ based option.