K3ii Astrophotography
Posted 10/08/2016 - 23:37
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Linked off my FB page. This is one I shot a few days ago. Bulb, 2 minute exposure, locked cable release. Like you, I turned the GPS on, activated the astrotracer and did it all manual. Didn't even see the max exposure warning, wherever that was!!


Gareth Williams ARPS
My outfit: K1ii - Pentax D FA 24-70mm f2.8 - Pentax DA* 300mm f4 - Pentax modified DA* 60-250mm f4 - Irix 15mm Firefly - Pentax FA 35mm - FA 50mm f1.4 - Tamron SP 90mm macro - Pentax AF 540 FGZ II
Welsh Photographer
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My PPG
Foundation NFT
My outfit: K1ii - Pentax D FA 24-70mm f2.8 - Pentax DA* 300mm f4 - Pentax modified DA* 60-250mm f4 - Irix 15mm Firefly - Pentax FA 35mm - FA 50mm f1.4 - Tamron SP 90mm macro - Pentax AF 540 FGZ II
Welsh Photographer
Flickr
My PPG
Foundation NFT
Posted 10/08/2016 - 23:53
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Wow what an awesome photo!
What settings if you don't mind me asking?
What settings if you don't mind me asking?
Posted 11/08/2016 - 06:32
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Paul - just a thought - did you cover the viewfinder as any stray light could well seep in there during a long exposure.
Andy
Posted 11/08/2016 - 08:10
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alfpics wrote:
Paul - just a thought - did you cover the viewfinder as any stray light could well seep in there during a long exposure.
Paul - just a thought - did you cover the viewfinder as any stray light could well seep in there during a long exposure.
No I didn't.....didn't know I was supposed to! so that would be for part of the exposure I assume, are there any rules here? Half the exposure....a few seconds?
Posted 11/08/2016 - 12:11
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Hi Paul
The problem with long exposures is that any residual light around the viewfinder can get through and onto the sensor. So, eg, if you had a torch on behind the camera whilst you were night shooting, its light would be significantly brighter than what is coming from the sky. There was a thread about this recently
link
All you need is either the cap which came with the camera, although that is fiddly to fit in the field, so a bit of dark cloth or something and leave it there for the whole exposure
Hope that helps
The problem with long exposures is that any residual light around the viewfinder can get through and onto the sensor. So, eg, if you had a torch on behind the camera whilst you were night shooting, its light would be significantly brighter than what is coming from the sky. There was a thread about this recently
link
All you need is either the cap which came with the camera, although that is fiddly to fit in the field, so a bit of dark cloth or something and leave it there for the whole exposure
Hope that helps
Andy
Posted 11/08/2016 - 12:17
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alfpics wrote:
Hi Paul
The problem with long exposures is that any residual light around the viewfinder can get through and onto the sensor. So, eg, if you had a torch on behind the camera whilst you were night shooting, its light would be significantly brighter than what is coming from the sky. There was a thread about this recently
link
All you need is either the cap which came with the camera, although that is fiddly to fit in the field, so a bit of dark cloth or something and leave it there for the whole exposure
Hope that helps
Hi Paul
The problem with long exposures is that any residual light around the viewfinder can get through and onto the sensor. So, eg, if you had a torch on behind the camera whilst you were night shooting, its light would be significantly brighter than what is coming from the sky. There was a thread about this recently
link
All you need is either the cap which came with the camera, although that is fiddly to fit in the field, so a bit of dark cloth or something and leave it there for the whole exposure
Hope that helps
Thanks,
So I need to take 2 exposures, one of the sky and one of the dark cloth? (same exposure length?)
Do I then just combine the images in something?
Posted 11/08/2016 - 12:42
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paulcliff wrote:
Thanks,
So I need to take 2 exposures, one of the sky and one of the dark cloth? (same exposure length?)
Do I then just combine the images in something?
alfpics wrote:
Hi Paul
The problem with long exposures is that any residual light around the viewfinder can get through and onto the sensor. So, eg, if you had a torch on behind the camera whilst you were night shooting, its light would be significantly brighter than what is coming from the sky. There was a thread about this recently
link
All you need is either the cap which came with the camera, although that is fiddly to fit in the field, so a bit of dark cloth or something and leave it there for the whole exposure
Hope that helps
Hi Paul
The problem with long exposures is that any residual light around the viewfinder can get through and onto the sensor. So, eg, if you had a torch on behind the camera whilst you were night shooting, its light would be significantly brighter than what is coming from the sky. There was a thread about this recently
link
All you need is either the cap which came with the camera, although that is fiddly to fit in the field, so a bit of dark cloth or something and leave it there for the whole exposure
Hope that helps
Thanks,
So I need to take 2 exposures, one of the sky and one of the dark cloth? (same exposure length?)
Do I then just combine the images in something?
No, you put the dark cloth over the viewfinder during the exposure. It is to stop light seeping in through the viewfinder.
There are plenty of tutorials online for astro photography. I play now and again, never managed a photo as good as Gareths, though I did get some good Milky Way ones in Death Valley.
Posted 11/08/2016 - 15:58
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As Gwyn says above.
It is the viewfinder (where you look through) at the back of the camera that needs to be covered. For some reason most cameras are not light tight here and so any light from near the rear of the camera can find its way in reverse if you like through the pentaprism and (I am guessing) around the sides of the raised mirror.
If you cover the viewfinder whilst making a long exposure, then you should not get light leakage affecting the image.
It is the viewfinder (where you look through) at the back of the camera that needs to be covered. For some reason most cameras are not light tight here and so any light from near the rear of the camera can find its way in reverse if you like through the pentaprism and (I am guessing) around the sides of the raised mirror.
If you cover the viewfinder whilst making a long exposure, then you should not get light leakage affecting the image.
Andy
Posted 11/08/2016 - 16:17
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paulcliff wrote:
Wow what an awesome photo!
What settings if you don't mind me asking?
Wow what an awesome photo!
What settings if you don't mind me asking?
Sorry, took a while to get in front of the PC and read the EXIF
DA* 16-50mm @ 28mm
ISO 800
f4
124 sec
Not sure if these are the desired settings but they seemed to work ok
Gareth Williams ARPS
My outfit: K1ii - Pentax D FA 24-70mm f2.8 - Pentax DA* 300mm f4 - Pentax modified DA* 60-250mm f4 - Irix 15mm Firefly - Pentax FA 35mm - FA 50mm f1.4 - Tamron SP 90mm macro - Pentax AF 540 FGZ II
Welsh Photographer
Flickr
Instagram
My PPG
Foundation NFT
My outfit: K1ii - Pentax D FA 24-70mm f2.8 - Pentax DA* 300mm f4 - Pentax modified DA* 60-250mm f4 - Irix 15mm Firefly - Pentax FA 35mm - FA 50mm f1.4 - Tamron SP 90mm macro - Pentax AF 540 FGZ II
Welsh Photographer
Flickr
My PPG
Foundation NFT
Posted 11/08/2016 - 16:29
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Ahh, viewfinder, that's me not paying attention sorry, I'm with you now!
Thanks for the settings Gareth, I'll have a play tonight whilst watching the meteor shower (if the weather is kind to me).
Thanks everyone for your help...results to follow.
Thanks for the settings Gareth, I'll have a play tonight whilst watching the meteor shower (if the weather is kind to me).
Thanks everyone for your help...results to follow.
Posted 11/08/2016 - 22:06
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Posted 11/08/2016 - 23:08
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Hi there is a astro group that's worth joining on the USA Pentax forum
cheers Neil
pentax k3
DA* 300 f4 DA* 50-135 f 2.8 smc DA* 16-50 f2.8 50mm f1.7 pentax1.4xhd converter
Panasonic Dmc Fz200
pentax k3
DA* 300 f4 DA* 50-135 f 2.8 smc DA* 16-50 f2.8 50mm f1.7 pentax1.4xhd converter
Panasonic Dmc Fz200
Posted 21/10/2018 - 20:29
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hello all
so with the astrotracer feature, does anyone know if the sensor still has a IR filter?
I have K10, K5, K3 ii, KP
so with the astrotracer feature, does anyone know if the sensor still has a IR filter?
I have K10, K5, K3 ii, KP
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192 posts
13 years
Kent,
UK
Can anyone share their experience with using it or help me in anyway with the general setup?
I basically pointed the camera at the sky, activated GPS and the astrotracer, it told me that 5mins was the maximum, I let it expose for 5mins and got a lovely white photograph of nothing.
I thought I could set my own exposure time, but the UI seems to indicate this deactivates the astrotracer?
In the end I left it in BULB which seemed to indicate the astrotracer was now on and just guessed how long I should expose for. It ended up being 118 seconds, and after some playing in Lightroom I got the following:
So it looks like the astrotracer is definitely working as there are no star trails, but the original image was so over exposed.
My settings:
118s | f2.8 | iso400
Should I be doing something like:
3mins | f10| iso200 ??
Thanks for any help!