Been given a DSLR and other equipment - advice on it needed for astrophotography

[Skyballer]

Hey!

I've been given a DSLR and some extras, but I'm new to photography in general so don't know much about it. I'd love to make a start in astrophotography though.

I can't afford too much extras right now, but going by this youtube video I'd love to make a start like this if it's possible:  https://www.youtube.com/watch?v=iuMZG-SyDCU&list=WL&index=11&t=0s

If anyone can advise on any extras I may need and or what I can / should use from what I already have that would be greatly appreciated. Thanks

The list:

Nikon D5300 Camera

Nikon AF-S DX NIKKOR 18-55mm f/3.5-5.6G VR Lens

Nikon AF Nikkor 50mm f/1.8d Lens

Nikon AF-S NIKKOR 70-300mm  f/4.5-5.6G SWM VR ED IF Lens 

The above lens appears to have a Jessops circular polariser filter 67mm on it which seems to be stuck on!

Hoya prond 1000 10 stops light loss 52mm filter

Another filter in a plain box, filter says ND Vario 2-400 52mm MMX on it

AmazonBasics Wireless remote control

Velbon DF 40 Tripod

4 Camera batteries / charger

 

Any advice on this lot and what's good to use / what I should look at buying would be appreciated.

 

[Waldemar]

Best advice? Buy yourself some books like these: http://astronomyonline.info/5-best-astrophotography-books/ and educate yourself

 

[wxsatuser]

With that setup you can do static widefield shots.

Exposures will be relatively short, depending on the lens but you can easily make a start in AP.
Try this for starters.
https://www.lonelyspeck.com/

[endless-sky]

You got a really good camera for astrophotography. The Nikon D5300 is one of the best APS-C DSLRs for the job. Yes, I am biased, as I have one as well. But I have also been using it for astrophotography for the past 6 months and I really like the results: low noise, high dynamic range, light body.

You can definitely start doing some static astrophotography with the lenses you have: the shorter the focal length you will use, the longer the exposure can be, before stars start to trail. Definitely do not use any filters that block light and try to unscrew the polarised filter - all these are not needed for astrophotography and might make things worse.

The D5300 is ISO-less, that means it doesn't matter at what ISO you shoot, so you should use the ISO that gives you the highest dynamic range: 200 ISO. Everything else past that just increases noise and diminishes dynamic range.

Take a lot of short exposures (short enough that you don't get star trails, with the given lens/focal length) and stack them with some free stacking program (DeepSkyStacker, for example). The more you stack, the better the result will be (up to a diminishing return limit).

Next upgrade, if you like the hobby and want better results, would be to buy a star tracker (for example, the Sky-Watcher Star Adventurer Pro): with that, you can raise your exposures and gather more data.

[Skyballer]

11 hours ago, wxsatuser said:

With that setup you can do static widefield shots.

Exposures will be relatively short, depending on the lens but you can easily make a start in AP.
Try this for starters.
https://www.lonelyspeck.com/

Thanks, I will check this site out!

10 hours ago, endlessky said:

You got a really good camera for astrophotography. The Nikon D5300 is one of the best APS-C DSLRs for the job. Yes, I am biased, as I have one as well. But I have also been using it for astrophotography for the past 6 months and I really like the results: low noise, high dynamic range, light body.

You can definitely start doing some static astrophotography with the lenses you have: the shorter the focal length you will use, the longer the exposure can be, before stars start to trail. Definitely do not use any filters that block light and try to unscrew the polarised filter - all these are not needed for astrophotography and might make things worse.

The D5300 is ISO-less, that means it doesn't matter at what ISO you shoot, so you should use the ISO that gives you the highest dynamic range: 200 ISO. Everything else past that just increases noise and diminishes dynamic range.

Take a lot of short exposures (short enough that you don't get star trails, with the given lens/focal length) and stack them with some free stacking program (DeepSkyStacker, for example). The more you stack, the better the result will be (up to a diminishing return limit).

Next upgrade, if you like the hobby and want better results, would be to buy a star tracker (for example, the Sky-Watcher Star Adventurer Pro): with that, you can raise your exposures and gather more data.

Thanks for taking the time to respond, done a ton of research yesterday, but didn't know about this ISO-less thing. I was set to go at 800 ISO, f/4 with 2 sec exposure time. You say to drop that to 200 ISO? Would 2 sec exposure and f/4 still be fine? 

Not sure which lens is best to use of the 3 I have listed? I'm guessing though just the Nikon AF Nikkor 50mm f/1.8d Lens - Then I can drop the aperture down? Or better with the 18-55mm lens? Think it was at about f/4 at 24mm. 

Edited August 1, 2020 by Skyballer

[happy-kat]

The 50mm lens is your fastest and you only need to stop down if it improves the star shape, as some lens show more star bloat and chromatic aberration (purple fringing on bright objects) fully wide open so you'll need to test if your lens needs stopping down and even if it does you may find just one or two stops is enough.

[endless-sky]

Well, I suppose it depends on the fact if data is getting clipped (not recorded) or not.

For example, if I can expose 20 seconds at ISO 200 without getting clipped (the histogram is detached by a good margin from the left, where 0 would be complete black), there would be no point in doing 20 seconds at ISO 400 (as this would only shift the histogram further right, without recording any more data). It would be equivalent of shooting 10 seconds at ISO 400 (or pretty close), but then you would be losing dynamic range.

This works perfectly fine if I have a tracking device that can expose for 20 seconds, at a given focal length, without star trails.

In the case of static shooting, you actually have to find a combination that works good enough: short enough that you don't get star trails, long enough that the histogram is detached from the left (otherwise clipping). If this exposure time is not enough to detach the histogram at 200 ISO, then you will inevitably have to compromise a little on the dynamic range and try 400 or even 800 ISO.

The generic "rule" to calculate static exposure is 500 / focal length = maximum number of seconds in order to not get star trails. I tried this, but it is not entirely true. I found that I need to further shorten the time. For a 50mm I found that I could go up to 8 seconds, for example, when I shot the comet from a dark place and I couldn't bring my mount with me. But it also depends by how much away from the North Celestial Pole you are shooting (the closer you are to it, the less stars move for a given time, while the further away, the more they move), so you'll have to adjust the exposure even more.

I guess all I can tell you is to experiment and check the screen on the back of the camera until you find a combination that work.

Edited August 1, 2020 by endlessky

[Skyballer]

Thanks, I'll see how I get on when the skies are clear next. 

I live in the Scottish highlands, right by a dark sky park which is nice, I believe they are quite rare. 

[happy-kat]

I use both a static mount and a tracking none equatorial mount, the favourable directions to point are East or West and the lower the better. Shooting South or North shows star trails faster and faster still the higher up you point.

Edit: the lower you point the more murk atmosphere so that's a consideration as well..

You'll either need to use the onboard timer delay or get a remote shutter release.

Have fun learning to use your camera.

Edited August 1, 2020 by happy-kat

[Skyballer]

Should the Long exposure NR and High ISO NR be on and if yes what setting for high iso nr?

Also say I want to take 30 x 6 second long exposures. I set the shutter speed to 6" then in the settings, interval timer shooting the interval time, do I set that to 6 or does it need to be higher? 

 

**Just tested the interval time and although I selected a shutter speed of 6 seconds on manual mode, when I went into the interval timer shooting in the settings, 6 or 7 seconds with 3 pictures as a test resulted in it only taking 2 pictures? Had to bump that to 8 seconds to get 3 photos. 

How do I know the correct interval time to set relating to my shutter speed? As when I get a samyang 14mm lens i'd be able to bump shutter speed up to 20 sec. 

Edited August 4, 2020 by Skyballer

[jiberjaber]

29 minutes ago, Skyballer said:

Should the Long exposure NR and High ISO NR be on and if yes what setting for high iso nr?

Also say I want to take 30 x 6 second long exposures. I set the shutter speed to 6" then in the settings, interval timer shooting the interval time, do I set that to 6 or does it need to be higher? 

 

**Just tested the interval time and although I selected a shutter speed of 6 seconds on manual mode, when I went into the interval timer shooting in the settings, 6 or 7 seconds with 3 pictures as a test resulted in it only taking 2 pictures? Had to bump that to 8 seconds to get 3 photos. 

How do I know the correct interval time to set relating to my shutter speed? As when I get a samyang 14mm lens i'd be able to bump shutter speed up to 20 sec. 

No - turn them off else you'll be there for ages whilst the camera duplicates the exposure to try and make a dark frame and internally process that.  Better to do that where you have more control on a PC

[happy-kat]

6 hours ago, Skyballer said:

How do I know the correct interval time to set relating to my shutter speed? As when I get a samyang 14mm lens i'd be able to bump shutter speed up to 20 sec. 

That's what cloudy days are for so you can practice and learn your camera when time isn't critical

[endless-sky]

7 hours ago, Skyballer said:

Should the Long exposure NR and High ISO NR be on and if yes what setting for high iso nr?

Also say I want to take 30 x 6 second long exposures. I set the shutter speed to 6" then in the settings, interval timer shooting the interval time, do I set that to 6 or does it need to be higher? 

Definitely turn off any "in-camera" noise reduction. If you want to calibrate the images, taking proper darks works better: just take 20-25 dark frames at the same exposure time that you took the lights and integrate them into a master-dark, which then will be subtracted from the lights during the calibration phase. Long exposure noise reduction does this after each light, but only takes one dark and subtracts it: an average of 20-25 darks works much better.

With that said, I believe taking darks with a thermally uncontrolled DSLR could actually do more harm than good. Noise is very sensitive with temperature and if the temperature of the sensor/camera while taking the lights is not the same while taking the darks, the noise of the darks won't match the one in the lights, resulting in more noise actually being injected in the calibrated frame. This is another aspect where dedicated and cooled astrocameras shine with respect to regular DSLRs: the ability to control the temperature with very good accuracy and repeatability.

To control the sequence of exposures, consider investing in an intervalometer. They are relatively cheap (less than 20 Euros) and you can program the entire sequence: exposure length, number of exposures, delay between shots. Amazon has many examples, just make sure you buy one that is compatible with your camera.

Another tip is to turn on the in-camera setting called delay exposure: this is useful because the camera will start recording the picture about 1 second after the mirror has been lifted up (this reduces the possibility of vibrations ruining the long exposure). Just take into account that the 1 second is part of the total exposure time you chose (so, if you want a 5 second exposure, with the delay exposure setting on, you'll have to program a 6 second exposure, instead).

Edited August 4, 2020 by endlessky

[Skyballer]

Thanks for all the tips guys. I got the interval timing down yesterday, seems an additional 2 seconds works well. 

I've been taking about 30 darks right before I start my lights.

I assume I can reuse old bias frames but what about flats? 

[Tenor Viol]

OK - that's pretty decent kit. To get the polariser off, get one of those non-slip grip mats that you can use for opening jars etc. Polarisers can be fiddly because there is the front rotating element and the rear element which actual screws into the filter thread on the lens. It can be hard to get a grip on them which is why I suggest one of those rubber type mats. 

You can take static tripod shots for Milky Way and constellation. Use the '500 rule': 500 divided by the focal length in mm gives maximum exposure time without trailing. The 50mm lens is your fastest at f/1.8. But the D5300 is a DX 1.5x crop sensor APS-C camera, so it will behave as a 75mm full frame equivalent. This means you 500 rule is 500/75 = 6.5 seconds. 

A star tracker would be the logical next step to enable you to take much longer exposures and you'd be able to use much longer focal lengths.  

[Skyballer]

1 minute ago, Tenor Viol said:

OK - that's pretty decent kit. To get the polariser off, get one of those non-slip grip mats that you can use for opening jars etc. Polarisers can be fiddly because there is the front rotating element and the rear element which actual screws into the filter thread on the lens. It can be hard to get a grip on them which is why I suggest one of those rubber type mats. 

You can take static tripod shots for Milky Way and constellation. Use the '500 rule': 500 divided by the focal length in mm gives maximum exposure time without trailing. The 50mm lens is your fastest at f/1.8. But the D5300 is a DX 1.5x crop sensor APS-C camera, so it will behave as a 75mm full frame equivalent. This means you 500 rule is 500/75 = 6.5 seconds. 

A star tracker would be the logical next step to enable you to take much longer exposures and you'd be able to use much longer focal lengths.  

The polariser is on the 70-300mm lens so haven't bothered with it, as the 50mm with its f value suits me well. But saying this, I got hooked fast and have just bought a Samyang 14mm f/2.8 ultra wide lens  

As you say, my next step will be a tracker. But at least with the Samyang I can now do up to 20 sec exposures (that factors for the cropped sensor on my camera). 

[Tenor Viol]

3 minutes ago, Skyballer said:

The polariser is on the 70-300mm lens so haven't bothered with it, as the 50mm with its f value suits me well. But saying this, I got hooked fast and have just bought a Samyang 14mm f/2.8 ultra wide lens  

As you say, my next step will be a tracker. But at least with the Samyang I can now do up to 20 sec exposures (that factors for the cropped sensor on my camera). 

I have a Nikon D7500 and a Z6 and use a Sigma 10-20mm lens for really wide and a Nikon 24-70mm f/2.8 - the Z6 is full frame so 24mm is quite wide