Yup I stumbled upon astrometry a few days back and that's amazing to know. Seems like doing AP stuff manually and with less expensive gear is not really too much of a headache nowadays.Devin-M said:
I don't want to get sucked into the spending hole, so this is an inspiration :)sophiecentaur said:
No problem any more with registering multiple images; software will do that for you (even when the mount is not equatorial). The can still be a problem with star trails from long exposures and long exposures beat multiple exposures for really faint objects.PhysicoRaj said:
Heard that long exposures have less bias / read-out noise compared to sub-exposures. And, for the reason Devin-M mentioned, making full use of one perfect night / travel means I should be taking in as much signal and less noise as possible, which is possible with tracking (at least manual, nightmare in an alt-az mount).sophiecentaur said:
What would that be in f number, altogether? I think your solution would be 'unusual' so it could be worth submitting the idea to a couple of dedicated astro forums (like stargazers' lounge). Making almost simultaneous exposures would probably be best on a common, heavy duty mount.Devin-M said:
Slippery slope here. That's why people buy dedicated astro cameras with Peltier cooling. There's really no substitute for that when you start to get really fussy.PhysicoRaj said:
Oops. I have started a project on peltier cooling my DSLR because I already have a couple modules and heat sinks lying around. But I am trying to avoid 'breaking-in' to my camera (warranty) and finding a way to cool it non-invasive, like at the backside where the flip-screen fits, or in case the mounting hole at the bottom connects to the sensor shield somehow, forms a thermally more conductive path.sophiecentaur said:
There's a possible way in, via the optical tube. A waft of cold air passing over the sensor would cool it. But you'd need a glass window (coated etc) to stop the objective getting dew on it if the cold air got up that end.PhysicoRaj said:
They're very expensive here. I already carry my DSLR around for hikes and I can easily set it up for an astroshot, without a laptop.sophiecentaur said:
sophiecentaur said:
Yes the narrowband filters let almost no light through so each exposure is around 5 minutes even if you set the ISO sensitivity very high. Also, they make it impossible to use the viewfinder or live view so the only way to frame the shot that I’ve found is by taking test shots and then uploading them to http://nova.astrometry.net/upload for plate solving.PhysicoRaj said:
Devin-M said:
Its LED here, does that mean even standard light pollution filters would not work? My camera is unmodded, so I wouldn't be able to use the NB filters but I was thinking of an LP filter.Devin-M said:
LED spectrum is broadband so the sky will be glowing in whatever wavelengths your light pollution filter let's through.PhysicoRaj said:
Bittersweet, that prevents me from spending on another accessory but its hard to find a darker area. My area now is a Bortle 5 - 6 according to clearoutside.com but there is some localized LED pollution.Devin-M said:
My camera is unmodded but I still use the narrowband filters… as far as I understand it the wavelengths the narrowband filters allow to pass through are in the visible spectrum.PhysicoRaj said:
What happens if you add something like this into the mix… that should in theory get you up to 2100mm f/36…PhysicoRaj said:
Even the H-alpha? I have seen some people do a full spectrum mod and even use UV narrowband on some targets. But I did not know that narrowband imaging in Visible wavelengths is going to add something extra. Have to read up on that.Devin-M said:
I cannot use a teleconverter as I am sticking my DSLR into my scope focus tube for planetary. Or so I think. But, I do have a 3x barlow that will give me 700x3=2100mm focal length, but that is too much for the moon. Also I am finding that much magnification a little lossy, not sure if I am over-magnifying or its just the low quality of the barlow.Devin-M said:
Yes H-alpha is visible light.PhysicoRaj said:
Wow. Never thought a stock DSLR would be so capable. I thought the H-alpha is 100% blocked out by the stock IR-cut filter in front of the sensor.Devin-M said:
From what you say, your wallet has limited capacity (join the club!). That means you need to profit from the mistakes of others. Just follow some of the 'beginner' threads in astro forums. There are very experienced AP'ers who have been through it all before and their recommendations are really worth taking seriously. Time spent doing this will probably be worth at least 'the minimum wage' for you (and with no income tax involved).PhysicoRaj said:
OP needs to read all the reviews on trackers. There are good ones and not so good ones. People often use a tracker to start with and move on up. So you can expect to find perfectly good s/h ones at good prices.Devin-M said:
I have traveled along that riverbank a couple of times during the day, and that place is sandwiched between two reserved forests and it might get scary at night (I could hear a faint tiger roar occasionally at dusk when we stopped for waterDevin-M said:
).Because you have thrown away, effectively, about two thirds of the light entering each camera because of the filters, you are back where you started. With narrower band filters, you are losing even more light; people need long exposures to reveal the low levels of Hydrogen lines in some DSOs. The pictures are pretty and impressive but not 'reality'.Devin-M said: