Guiding - Webcam sensitivity?

[JimS]

Didnt seem to get any response in discussion so I have added this thread to Getting Started - 

 

I have done a little bit of manual guiding using my Logitech webcam through a StarTravel 80, but this has been imaging Orion Nebula where there is an easy bright guide star to use.

 

Last night, I tried to venture further and have a go at other targets such as Pinwheel galaxy and Whirlpool Galaxy. Both times I could not find a guide star at all through the webcam using SharpCap. I was initially going to use this as a test and then have a go at using PHD for the first time, however gave up as I just couldn't find a guide star and just did a couple of 30 second unguided images.

 

The webcam can pick up brighter stars such as Capella and Procyon (used these as part of my alignment process) but really seems to struggle on anything else, even with frame rate, exposure and gain pushed as far as they'll go. Would PHD be able to push the exposure of the webcam to be able to pick up stars or am I going to struggle from the outset? If so is there a cheap(?!) entry level guide cam available out there that someone could recommend?

 

Cheers

 

Jim

[Cozzy]

Jim,

I also use the SW 80mm for guiding, I have an SPC880 camera and use wxastrocapture to do my FOCUS and gain and then switch to PHD for guiding.I find it is quite easy to fly by low magnitude stars when focusing but does pick them up given care and attention with focus. I find if I can see them in my 50mm finder I can pick them up with SPC880.

hope this helps a bit.

Tim

[Leveye]

I use an older Meade DSI1 mono that i picked up for a song.Works great with PHD2.

[Cozzy]

Sorry forget to say I also use the SPC880 with the 50mm finder, a little more difficult but still works ok.

Tim

[jimbo747]

A £5 ps3 eye camera will do 10s exposures - plenty I reckon to guide on dimmer stars.

[toxic]

i use the micosoft lifecam 3000 hd i have the logitech c300 and it is ok but not as sensitive as the lifecam or the ps3 eyetoy but you should have been able to get at least 1 guide star with the c300.

forget sharpcap for now and  use phd then go into camera dialogue and increase the exposure.it should be ok 

[JimS]

Cheers for responses. I've got a PS3 camera for under £5 on eBay. Will give this a go. Presumably once the windows drivers are installed PHD will see it as a standard webcam?

[jimbo747]

Yup, you might need the SDk to get access to longer and shorter exposures though as well as the driver. If you have any issues don't email the developer, he never bothers responding to my technical question emails.

[JimS]

Had one of those nights you would rather forget last night. Managed to get a good polar alignment approximation through my polarscope, and got everything set up and then it seemed to go wrong from there. Couldn't even get my CGEM to align and calibrate properly even though I have done it many times before, just didn't seem to want to play. Gave up in the end and just manually drove to targets.

Then the main issue started arising with the PS3 camera that I have acquired. The camera seemed very, very noisy and I still couldn't seem to find any but the very brightest stars ie Vega, Capella. What sort of settings are people using for the PS3 camera; is there a routine to go through such as setting it up in camera software first before opening PHD. Then my laptop kept crashing out about a minute after turning on the PS3 camera. It did it in PHD, SharpCap and the PS£ driver program. Has anyone else experienced this?

Thanks for any help.

[Cath]

You'd be far better off using a camera with a mono sensor. It would give you better sensitivity and higher resolution (assuming same number of pixels).

[JimS]

Hi Cath

That's not really an option at the moment as I can't really afford one. There have been some cracking results from PS3 eye cameras, I just seem to be missing something.....!

Cheers anyway.

[jimbo747]

Not all ps3 eye cams are made equal - in fact I think there are at least 2 different types. Some of them are incredibly noisy/show amp glow (pure green pixels at 10s, no gain, at 4s covers approx 1/4 of the sensor - practically useless), other ones show no noise at all (I hand pick these ones and send others back). Out of approx 50 cameras only 2 have shown no noise at all with the exposure at 10s, rest seem to have a little (loads if gain is used0, and others have awful amp glow. I tend to leave gain at minimum and just increased exposure, you'll get best results that way.

Apparently you can also debayer a ps3 eye cam fairly easily, might try that next. Someone on here did some fantastic lunar images with one.

You using the SDK too?

Never had the crashing though, I'd try reinstalling the .net libraries..

[JimS]

Not all ps3 eye cams are made equal - in fact I think there are at least 2 different types. Some of them are incredibly noisy/show amp glow (pure green pixels at 10s, no gain, at 4s covers approx 1/4 of the sensor - practically useless), other ones show no noise at all (I hand pick these ones and send others back). Out of approx 50 cameras only 2 have shown no noise at all with the exposure at 10s, rest seem to have a little (loads if gain is used0, and others have awful amp glow. I tend to leave gain at minimum and just increased exposure, you'll get best results that way.

Apparently you can also debayer a ps3 eye cam fairly easily, might try that next. Someone on here did some fantastic lunar images with one.

You using the SDK too?

Never had the crashing though, I'd try reinstalling the .net libraries..

I've not downloaded / used the SDK. I managed to SharpCap to adjust the framerate and therefore exposure time but obviously this is useless when the noise is there. Is there anyway of telling if the camera is good/bad from a model no? Is it just blind luck?

[JimS]

Quick stupid question but does the eyecam save the preview frames to memory? Would this cause a crash?

[Cath]

That's not really an option at the moment as I can't really afford one. There have been some cracking results from PS3 eye cameras, I just seem to be missing something.....!

Hello Jim. Not being able to afford the tools/toys I totally understand, as do most others, so don't worry !! .. It's all to easy to end up in debt after seeing others (very few when you count the forum ID's) on the forum having the toys they want. My 'bad'.

[JimS]

Hello Jim. Not being able to afford the tools/toys I totally understand, as do most others, so don't worry !! .. It's all to easy to end up in debt after seeing others (very few when you count the forum ID's) on the forum having the toys they want. My 'bad'.

No worries. Should be in a position to get my grubby mitts on one early next year hopefully.

for the moment i'm just irritated because the PS3 cam I have seems to be pretty poor compared to others. However the comment regarding two 'types' is interesting.

[Cath]

Should be in a position to get my grubby mitts on one early next year hopefully.

OK ......... 'should' is a word that 'should' be stricken from the human language

irony (we all do it) speaks for itself, given time