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Forum: Pentax K-5 & K-5 II 04-18-2018, 05:07 AM  
K-5 For Astrophotography
Posted By geo444
Replies: 1,118
Views: 314,704
.
To answer the "what else" question, I summarized :
- the Top-8 Cameras with lowest Detection-Threshold < 0,01% @ 0dB SNR, from DxOmark
same as in my previous post, ordered by Measured-ISO
- the Top-8 Cameras with lowest Noise-Levels in 5 min. Dark-Frames
from The Sensor Noise DB. – Brendan Davey Photography
ordered by their Noise-Mean-Value

Pentax K-1, the 95 Top Measured-ISO with a Detection-Threshold of 0,009% @ 0dB SNR
+ the 2nd Noise-Mean-Value just behind the Pentax K-5 in 5 min. Dark-Frames (+5ev)

The very Low Dark-Current levels of the Sony imx071 explain the Pentax K-5 Top position
= the 1st lowest Noise-Mean-Value in the 5 min. Dark-Frames (+5ev) test
the Dark-Current Chart is from the Zwo Astro imaging site :
https://astronomy-imaging-camera.com/products/asi-cooled-cameras/asi071mc-pro/
Same Sony sensor, at a $1700+ price !

Then the Asi071(K-5) compared to the Asi294 and Asi1600
= two Astro-Cams with 4:3 ~22,7mm diagonal sensors

High ISO settings are mandatory to lower the Exposure Time to 1 sec. or less
this to cancel the Atmospheric Turbulence effect with long FL.
the only way to operate with Lucky Imaging !

But finally, what do you lose from Base-ISO to ISO 10K :
- Dynamic Range value from 14 ev down to 7 !
- Tone Values from 16384 down to 128 !
- SNR to be Half the Base ISO SNR
- your RAW File Size doubles
- for the same final IQ, you'll have to Stack much more RAWs...
- with Dark-Frames !
Forum: Pentax K-5 & K-5 II 06-22-2020, 01:29 PM  
K-5 For Astrophotography
Posted By geo444
Replies: 1,118
Views: 314,704
.
Another set of 6 .PEF files I had some time to Rebuid from start...
are the 6 Exposures of 630 sec. each at ISO-80 from M-45 with the Pentax K-5
- the first version was made from 3 .PEFs only :
Pleiades M45 Pentax K5 geo444 Galleries Digital Photography Review

The fact that I erased my SD-Card between the 2 nights has resulted in Double-Crossed Stars...
I couldn't restore the Exact Camera Position on my S-W 200/1000 :lol:
= No Special Effect Filters were used !

Colors, Noise wise, the last 6 .PEFs version is far better :


.

A much larger M-45 picture, 2296 × 1528 is pixel-peepable here :
https://en.astronomike.net/1252091.jpg?20200611

... or with its Datas here :
Messier 45 - Pentax K-5 @ ISO 80 : 6 x 10 min. - SkyWatcher 200/1000 - Clusters AstronoMike.net
M45 - Pentax K5 iso 80 : 6 x 10 min - SkyWatcher 200/1000 - Clusters AstronoMike.net

... else you could also inspect it here :
Pentax K5 M45 Pleiades geo444 Galleries Digital Photography Review

Enjoy... :cool:
Forum: Pentax K-5 & K-5 II 04-15-2020, 12:11 PM  
K-5 For Astrophotography
Posted By geo444
Replies: 1,118
Views: 314,704
...
I had some time to rework these 3 old .PEFs from start to a better picture...
= the faintest stars get rid of the redish noise, completely :
.

.

A much larger M-13 version, 2304 × 1568 is pixel-peepable here :
https://en.astronomike.net/1247739.jpg?20200415

... or with its Datas here :
Messier 13 - Pentax K-5 @ iso 80 : 3 x 10 min - Proto DIMA 254/1200 - Clusters AstronoMike.net
M13 - Pentax K-5 iso 80 : 3 x 10 min - Proto. 254 / 1200 - Clusters AstronoMike.net

... else you could also pixel-peep it here :
https://www.dpreview.com/galleries/7467909648/photos/4058270/m13-hercules-pntx-k5

+ At the lower right of M-13... you can also see :
- IC- 4617 Magnitude ~15 Size ~1,1' x 0,4'
- Ngc6207 Magnitude 12 Size 3'x1,1'

Enjoy... :cool:
Forum: Pentax K-5 & K-5 II 03-11-2020, 12:12 PM  
K-5 For Astrophotography
Posted By geo444
Replies: 1,118
Views: 314,704
.
+10 ! ;)

What, 352 days since the last AstroPhotography has been posted,

I can't wait to post 3 of my first Astro-Shots taken with this Pentax Champion,

Hercule Cluster, shot 3210 days ago, K-5 at ISO 80 setting on a SkyWatcher 254/1200 :

A large M-13 version, 2208 × 1536 is pixel-peepable here :

https://en.astronomike.net/1240634.jpg?20110529
.
Forum: Non-Pentax Cameras: Canon, Nikon, etc. 11-03-2020, 05:29 AM  
1 inch sensor club
Posted By geo444
Replies: 261
Views: 25,981
.

People living in M51, if there is any, are taking a look at our Earth through a Giant Telescope and they just see Brontosaurs,
Dinosaurs, Tyranosaurs, one " Whirlpooler " says to his friend « you see, nothing that looks like clever livings on Earth ! » :o
.

M-1 Crab Nebula, apparent size 6'x4' magnit. 8,5 is only 6500 Light-Years from Earth ! It's the remains of the summer 1054
explosion of a SuperNova, Chinese astronomers said it was 6 times brighter than Venus and about as brilliant as the full Moon.
.
F11+ Right Click + View Image :


.

Messier-1 : Sky-Watcher 254/1200 + Samsung NX-mini at prime focus - No Filters used,
ISO 400 = 30 subs of 4 min. each Stacked + Levels to Highlight these Green Extensions.
2020 winter's weather conditions were totally appalling ( Windy ) hence the inflated stars.
I am the only one to show these Green Extensions around the left side of Crab Nebula !
.

How to do Astro-Photography with very little money :
Electro-Opto-Mechanical DIY to improve Pentax, Samsung cameras...
No cookies, 100% free site !

;)
Forum: Non-Pentax Cameras: Canon, Nikon, etc. 11-02-2020, 07:18 AM  
1 inch sensor club
Posted By geo444
Replies: 261
Views: 25,981
.
Bravo : Splendid pictures here ! Especially Dogs, Landscapes, Mushrooms from Normhead,
Snow, Tree, Flower from Wpresto ( since P.3 " la Rose Trémière Mauve " ! ), etc...

Here is one of mine, from 37 Million Light-Years in Deep-Space...
2 Galaxies which are Meeting like... Hairy Monsters ?

30 Exposures of 4 min. each stacked
Samsung NX-mini, ISO 400
Messier-51 b+a :
.

.

Other details and sizes here :
https://www.dpreview.com/galleries/7467909648/photos/4098937/m-51-a-b-nx-mini

Enjoy ! ;)
Forum: Non-Pentax Cameras: Canon, Nikon, etc. 11-06-2020, 03:49 AM  
6x6 SLR systems under $1,000 - Bronica S2, Kowa Six, Mamiya C220
Posted By geo444
Replies: 24
Views: 1,361
.
Good : it's the very Affordable and Reliable entry level model ! :cool:


.
That is not a final problem !
Each PS Lens you'll buy later will work in Time (T) Mode
.
Forum: Pentax Q 10-06-2020, 08:05 AM  
Now you can order a Metabones K to Q Speedbooster!
Posted By geo444
Replies: 108
Views: 7,979
.
If you need Long Exposure of 30 sec. for... hem... AstroPhotography ?
Photos tagged with "pentax-q10": Galleries: Digital Photography Review : Digital Photography Review
https://www.pentaxforums.com/forums/members/38890-geo444/albums/7415-photos-tests/
... it is a Mandatory Purchase !


.
As long as the Pentax Q could reach the 30 sec. Long Exposures in Electronic Shutter Mode...
... I think an Adapter could Simulate a Leaf Shutter without including one !
It just have to reply to the Q Body with the appropriate Signal...
= Through the Q Mount Electronic Contacts :
- Ok, Leaf Shutter Opened
- Ok, Leaf Shutter Closed

That may be a Very Interesting DIY Experiment...
~> see Q-Shutter.png attachement from
Pentax Q-S1 Review - Specifications | PentaxForums.com Reviews


.
I think from Q Mount to K Lenses, neither Autofocus nor Aperture Signals are Fully Compatible ?

For that price... at least, the Tripod Mount could have been included ! :cool:
.
Forum: Pentax Q 09-28-2020, 12:40 PM  
Pentax Q for astrophotography beginner?
Posted By geo444
Replies: 84
Views: 18,688
.
Wow !... Impressive Landscape under the Milky-Way !
... Was your Q-S1 w/o IR-cut filter or the night Not 100% Dark, or both ?
Is this place lit by the Light-Pollution ?


.
Is your scope a 1000mm Pure Reflector : Tube Length = ~900 mm~
... or some kind of " Catadioptric " Scope with Lenses in the focuser = Short-Tube ?
Catadioptric Reflector with Lenses in the focuser - Google Search

/!\ the Glass Element in the Focuser could be :
- some kind of Barlow Lens, could be Removed if you lengthen the tube ?
- some kind of Corrector that allows the use of a Spherical Mirror instead of a Parabolic one...
if you remove this Corrector, image borders will be blurred !
I hope it's Not one of these :
Black list of telescopes. Bad telescopes not for beginner

Tasco Galxsee 144500 Corrector ?
https://www.pentaxforums.com/forums/136-pentax-q/369368-pentax-q-astrophotog...ml#post4931112
it's not said that it has that Spherical Primary Mirror, so...
you still get one chance...
.

I wasted all the summer nights installing my Astro Gear in the yard of the building...
... and once everything was Well Settled and Ready for Astro-Photo...
the Clouds were Filling the sky from ~10 PM to ~2 AM !
:hmm: angry with all these climate skeptics

Nebulosity-Map history, location SE Marseille :
https://www.meteociel.fr/observations-meteo/nebu.php
some clear skies near the Full-Moon

So I came back to my site and completed some useful infos
1"25 Astro Filters inside Pentax K2Q Adapter
= how about 1"25 Filters in the Pentax K2Q adapter

Not even 1 astro-photo to post !
Forum: Pentax Q 09-28-2020, 01:52 PM  
IR infra red conversion for Pentax Q cameras
Posted By geo444
Replies: 29
Views: 19,062
.
Hand shaving the Bayonet Mount to be Perfectly Parallel is not so difficult...
... it would just take a somewhat longer time to achieve...
0,02 mm precision to be expected !


.
With or without the IR-cut filter in place, I think it's difficult to clean in both cases ?
... I always put a cap or a lens on my Q-10 to keep it clean !


.
AR Multi-Coated glass is mandatory for Astrophotography purpose :
... you often get Very Bright Stars in the frame, so...
you'll get Strong Light-Reflections between an Ordinary Glass & the Sensor's Glass !

> That's why I shaved my Q10's mount :
Pentax Q, Q-10 modified for IR-Landscape photography
... and, I am able to add every Astro-Filter :
1"25 Astro Filters inside Pentax K2Q Adapter


.
Congrats 2old4toys : #1 and #3 are Nice And Sharp !
+ isn't the #3 to show some... retro look ?

;)
Forum: Pentax Q 07-02-2018, 07:14 AM  
Pentax Q for astrophotography beginner?
Posted By geo444
Replies: 84
Views: 18,688
.
Thanks Dave ! ;)

DeepSkyStacker will not be a problem, it will simply do the job as usual :
http://deepskystacker.free.fr/english/userguide.htm
IMO, the simplest Stacking Tool

my BIG problem at Marseille is the Atmosphere's Stability
with your DA* 300mm on a Pentax Q, you'll see the Stars Blinking, Ok !
with a 1000mm you'll see the Stars Dancing...

( 1000mm on a Pentax Q = the same Reach as a Celestron C14 on an APS-C ! )

Many times, I've had to Trash ~ 50% of my 30 sec. subs ~
Here, the Sun Heats the Sea all the day long for more than 300 Days per Year,
at Night, usually the North Wind brings Cold Air over the Warm Sea !

The Precision / Sharpness of your Results depends on your Atmosphere's Stability...
- else it depends on your Determination to Trash every Blurred Sub ! :(

M-106 Galaxy : ~25 Million Light-Years from Q10 - apparent core size 2.5'x 6'
Magnitude minus Air- and Dust- and Light-Pollution worse than 10 ?
M-106 Galaxy : Q10 + SkyGlow Filter + Skywatcher 200/1000 = 88 x 30 seconds @ ISO 1600
Stacking = DeepSkyStacker 3.3



I highlighted 2 Stars close to the Galaxy :
- the Yellow one named USNOA2-1350-08095435 : Magnitude 17.3
- the Blue one named USNOA2-1350-08095450 : Magnitude 17.1
the distance in between is about ~8.5 arc second

Dumbbell gets More Pixels :
Messier 27 as seen from a Canon Eos 20d = 2.4 MPixel / cm²
-vs- shot by the Pentax Q10 = 44 MPixel / cm²
Both were shot at ISO 1600 :
https://www.dpreview.com/galleries/7467909648/photos/3037792/dumbbell-gets-more-pixels

Good Luck ! ;)
Forum: Pentax Q 07-02-2018, 12:55 AM  
Pentax Q for astrophotography beginner?
Posted By geo444
Replies: 84
Views: 18,688
.
The Pentax Q(x) with their tiny sensors are Not at their best for Wide Field Astro-Photography
for Wide Field, you'd better use an APS-C (or a FF) sensor !
+ you'd find more choice in (Ultra-)Wide-Angle lenses for large sensors (Samy)

But the Pentax Q(x) with their tiny sensors are at their Best for Long Reach Astro-Photography
Why ?
Simply because thousands of Deep Sky Small Objects will Never fill an APS-C sensor !
Even mounted on a very affordable SkyWatcher 1000mm Newtonian !
+ these tiny sensors are Very Sensitive ~ DxO ISO 5680 FF-Equivalent for the 1/2.3" in the Pentax Q, Q10 !

a Pentax Q10 w/ the Pentax Adapter on a Skywatcher 200/1000 Newtonian :
= 50 x 30 seconds @ ISO 1600 stacked with DSS 3.2
it's Messier 27 Nebula at 1350 L-Y :



Other (9) Long Reach Astro-Photographies taken with a Pentax Q10 :
The Astro-Q Club! - Page 10 - PentaxForums.com

Good Luck ! ;)
Forum: Pentax Q 05-10-2015, 09:13 AM  
The Astro-Q Club!
Posted By geo444
Replies: 193
Views: 75,463
.
M51 : Ngc-5194+5195 Whirlpool Galaxy

1st night = clear sky but Huge turbulence + the Full Moon near :
... once more, I had to discard ~50% of my shots !
+ yesterday, hazy sky but more quiet

M51 Whirlpool Galaxy : ~27 Million Light-Years from Q10 - apparent size : 6' x 9'
Magnitude minus Air- and Dust- and Light-Pollution is down to 10 !?
M51 Whirlpool : Q10 + SkyGlow Filter + Skywatcher 200/1000 = 84 x 30 seconds - ISO 1600 :
stacking : DeepSkyStacker 3.3 - finish : Elements 3.0




... in fact, it's not 1 Galaxy... but 2 ones which met each other !
the big Ngc-5194 has caught the little Ngc-5195...

the Q10 is not ridiculous vs the K5 which can hold 5 x 15 MINUTES total exposure at a noiseless ISO 80 !
... here are 4 photos of M51 Whirlpool Galaxy with Pentax K5 at the end of both pages :
http://www.chassimages.com/forum/index.php/topic,118675.75.html
http://www.chassimages.com/forum/index.php/topic,118675.100.html
the K5 was on a 254/1200 f/4.7 Skywatcher !

enjoy ! ;)
Forum: Pentax K-5 & K-5 II 07-24-2020, 01:08 AM  
K-5 For Astrophotography
Posted By geo444
Replies: 1,118
Views: 314,704
...
Now, if you find this last 6x10 min. version a little too much...
I recently built a 3x10 min. M45 with far less noise than the older version
here is this 3 Exposures of 615 sec. each at ISO 80 with the K-5 :
.

.

A much larger M-45 picture, 2296 × 1504 is pixel-peepable here :
https://en.astronomike.net/1251525.jpg?20200602

... or with the Datas here :
Messier 45 - Pentax K-5 @ ISO 80 : 3 x 10 min. - SkyWatcher 200/1000 - Clusters AstronoMike.net
https://en.astronomike.net/deep-sky/clusters/1376725.html
.

It just sits between the first Noisy 3x10 min. version :
Pleiades M45 Pentax K5 geo444 Galleries Digital Photography Review

... and the last Electric Blue 6x10 min. version :
Pentax K5 M45 Pleiades geo444 Galleries Digital Photography Review

Please, tell me which one do you prefer ?

;)
Forum: Pentax Q 04-13-2019, 09:13 AM  
Pentax Q for astrophotography beginner?
Posted By geo444
Replies: 84
Views: 18,688
.
220° Lens for the Pentax Q ?
4.2 mm Image Circle, more suitable for 1/3"-1/4" ?
At 2.1 mm from the center =~ about 37° Oblique Rays on the Pixels ?!
in the imx144 Specs, Sony measures Oblique Rays = 0-20°
and =~45° on the Protective Glass !?
.
Thus you'll have to Cut its IR-Filter-Box at less than 2 mm from the Sensor's Protective Glass !
... If you suppose the Sensor's Protective Glass to be 0.6 mm Thick :
http://mecastronics.free.fr/PentaxQ10AstroIR.html
( = the thickness of the IR cut Filter )
.

.
In the Kayak World, that wouldn't be too hard to get some friend lend you his Action Cam ?
One with 12 MP 1/2.3" sensor and the capability to record a Raw File...
... so you could evaluate the Aberrations ?
Especially the - Red Side - Chromatic Aberrations...
.
Can't wait to see the results...
;)
Forum: Pentax Q 07-04-2018, 12:42 AM  
Pentax Q for astrophotography beginner?
Posted By geo444
Replies: 84
Views: 18,688
.
Hi 2old4toys, what we know for sure is :

- Selecting Pentax 1/2.3 + 1/1.7 sensors in DxoMark DataBase we see
the 1/1.7" sensor has a 208 DxoISO score instead of ~280 as it's 50% larger than the 1/2.3" in the Q, Q10 :
Verification of the Direct Relationship from Sensor Area to DxoISO all other things equal
( Pentax Q + Q10 DxoISO = ( 183 + 189 ) / 2 = ~186 )

Can't go deeper with DxoMark as they didn't Test the Pentax Q7 & QS-1 :
My Comment on " DxoMarketing " : http://disq.us/p/1nnzyyb

- if the 1/1.7" sensor had the Starvis-Score of the 1/2.3" sensor
it should have a : 208 * 3354 / 2454 = ~284 DxoISO !
Starvis-Score & DxoISO seem Correlated
.

.

.
A CMos Sensor is a Highly Programmable Device, so
the only way to know What's the Sensor inside a Camera is to
look inside the FirmWare with an Hex-Viewer by downloading an Update
here is an example with the Q10 FirmWare
Verification of the imx078cqk
see attachment
.
Forum: Non-Pentax Cameras: Canon, Nikon, etc. 11-23-2019, 04:55 AM  
Samsung NX mini, a Top Infra-Red ILC for $125€
Posted By geo444
Replies: 11
Views: 6,149
.
Ladies, Gentlemen and Moon-Maids...
... here is the Image Quality one can get with a 1" BSI sensor !

I was somewhat helped by the Atmospheric Conditions : hazy and quiet...
- but the Colors - especially the Red and Blue - suffered a little
I couldn't get the amazing colors of the page top M27

The result is so detailed that I uploaded it in ~3000 x ~2000 pixels
-> you can watch the 3000 Pixels Wide Picture here :
Maxi Astro (Ciel Profond) au NX mini...
and also there :
M27, seen as if you were close : Digital Photography Review

= 30 .SRW Stacked, then Levels Push w/ Elements.3
Right-Click + View-Image + F11 to watch...
a half-sized preview of M27
.

.
Enjoy !

New infos about NX mini's imx183 BSI sensor :
Samsung-NX-mini-TOP-Infra-Red-ILC

;)
Forum: Non-Pentax Cameras: Canon, Nikon, etc. 10-08-2019, 05:50 AM  
Nikon 1 love?
Posted By geo444
Replies: 20
Views: 1,924
.
I think the idea of 1" ILC Cameras was good...
... but they should have got BSI sensors from start !
J5 got a BSI CMos sensor, but too late...

Taking a look at DPR-Tests tells us the same that DxO-Mark :
Samsung-NX-mini-TOP-Infra-Red-ILC
DPR Comparison is in the middle of the page

Let's see the Top Performances of a good CMos BSI 1" bare-sensor :
https://www.pentaxforums.com/forums/76-non-pentax-cameras-canon-nikon-etc/38...ilc-125-a.html

NiKon FSI 1" performances were too close to 1/1.7" & 1/2.3" BSI sensors...
... which are 4, yes four times smaller !
.
Forum: Pentax Q 08-20-2019, 04:39 PM  
IR infra red conversion for Pentax Q cameras
Posted By geo444
Replies: 29
Views: 19,062
.
Good Job ! Sincere Congratulations 2old4toys ! ;)



.
Sometimes, appearances are misleading ?...
Are you able to count the number of Dust Particles on your Photo #3, 1st Post ? :eek:
Particles are already visible on sensor... guess on a cover glass ?

I'm lazy... I choose the simpliest way to get the focus on sensor w/o any complication
... you just have to thin the bayonet mount... until the pictures are Sharp !
Reversible by putting a gasket of the exact thickness removed


.
Hi Barondla ! ;)
I too played with a microscope a long time ago when I was teen...
So I too had that idea, but...
- How to Clear the Particles off the inside of the Rubber Bellows, Post#1 Photo#3 ?
... of the sensor's Protective Glass ?... of the Cover Glass ?
- How to know the Refractive-Index of the Dichroic-Filter used by Pentax ?
... a special Dichroic Filter that let pass all the useful light througth
- How to fit the Cover Glass exactly parallel to the sensor ?
... once you've cut the ledges off the Filter Box...
- Everything is smaller than fingers !

That said... I would like to see the Difficults, hem.... Ooops ! No, the Results ! :lol:

After a looong Brain OverHeat... I was able to add 1 page to my site

Samsung-NX-mini-M48-or-M42-Mount-Adapter

Photos tagged with "nx-mini": Galleries: Digital Photography Review : Digital Photography Review

Good Luck, 2old4toys ! ;)
Forum: Non-Pentax Cameras: Canon, Nikon, etc. 07-24-2019, 03:55 AM  
1 inch sensor club
Posted By geo444
Replies: 261
Views: 25,981
.
This thread is a very good idea, rob1234, and...
... showing the Low Light capabilities of these 1" sensors an even better idea :
Camera Sensor Comparison Tools

--------------------------------------------------------------------------
How could we pass the idea to Pentax, for a... 1" BSI Q+ ?
... a Pentax 1" BSI Q+ MILC to be launched on November 27, 2019
the 100th anniversary of Asahi Optical Company
-------------------------------------------------------------

Sadly, for now, the NX mini is the only BSI one with interchangeable lenses
... Nikon J5 is too expensive for me and not able to hold 4 min. Bulb
the IR-Cut Filter is very easy to remove from the NX mini :
Samsung-NX-mini-TOP-Infra-Red-ILC
.
NX-mini 29 exposures of 4 min. at ISO 400 :
.

.
NX-mini 30 exposures of 4 min. at ISO 400 :
.

.
Astro-Photos up to 2000+ pixels wide with parameters from NX-mini :
geo444: Galleries: Digital Photography Review : Digital Photography Review
Members - Astronomy photos
Maxi Astro (Ciel Profond) au NX mini P. IV
Samsung NX mini, a Top Infra-Red ILC for $125
Maxi Astro (Messier 51) au NX mini page V

Early 2015 : the Highest Rated Canon APS-C camera had a... One inch Sensor ! :eek:
The Comparison that made me jump out to get a used NX-mini ASAP :
Camera Sensor Comparison Tools
.
Forum: Non-Pentax Cameras: Canon, Nikon, etc. 07-02-2019, 02:42 AM  
Samsung NX mini, a Top Infra-Red ILC for $125€
Posted By geo444
Replies: 11
Views: 6,149
Hi All Pentaxians ! ;)



... or maybe the full Moonlight + the fact I did not mount the SkyGlow filter ?

Yesterday, the sky was filling with clouds as soon as the night became dark for Astro...
... I stacked the 29 subs remaining (1 trashed ) in Kappa-Sigma mode,
which is designed to minimise Out of Range pixels Effect

The result is less noisy, so less NR needed
M-51 (Ciel Profond) au NX mini...
.

.
For now, it's the best... isn't it ?

Samsung-NX-mini-TOP-Infra-Red-ILC

Enjoy ! ;)
Forum: Non-Pentax Cameras: Canon, Nikon, etc. 06-18-2019, 03:05 AM  
Samsung NX mini, a Top Infra-Red ILC for $125€
Posted By geo444
Replies: 11
Views: 6,149
.
My last AstroPhoto : M-51 Whirlpool Galaxy
the Samsung NX mini mounted on a Sky-Watcher 254/1200 Newtonian
30 subs of 4 minutes each guided by Phd with a ToUcam

And the NX mini could achieve even Better Image Quality :
- here is a lot of Fixed Pattern Noise at 25° from the Vertical direction !
It couldn't be a problem from the imx183 sensor,
raw image noise due to electrical waves ?
Here is a 2000*2000 pixel M-51 :
Maxi Astro (Ciel Profond) au NX mini...
and more to read...



This in a well lit big city under the Full Moon ! :eek:

Samsung-NX-mini-TOP-Infra-Red-ILC

;)
Forum: Digital Processing, Software, and Printing 05-12-2019, 02:08 PM  
Camera Simulator, Exposure Calculator : SLV -25 to 30 Ev mini.
Posted By geo444
Replies: 6
Views: 2,804
.
In addition to the " Light Value " present in EXIF Datas,
this Utility SoftWare also Calculates the older " Exposure Value "
> just leave the ISO value unchanged at 100.

The 12 Action Links have been replaced by Buttons

The precision have been improved

The usable Range have been increased up to : -49 to 69 Ev-Lv

Camera Simulator, Exposure Calculator : SLV -49 to 69 Ev-Lv.

Left~Right side : Decrease / Increase Aperture, Shutter-Speed, ISO, SLV - Numbers

– / + : Decrease / Increase - amount of Light on sensor and/or image Brightness

Calc(ulate) : Aperture, ShutterSpeed, ISO, SLV from the 3 other values

3 Ev Steps: 1, 1/2, 1/3 --- 12 Scenes: Light Value –6 to 16 Ev-Lv

Camera Simulator, Exposure Calculator : SLV -49 to 69 Ev-Lv.

;)
Forum: Digital Processing, Software, and Printing 05-16-2019, 03:15 PM  
Hacking Exif with Exiftool
Posted By geo444
Replies: 39
Views: 5,791
.
Huge work with exiftool on Pentax EXIF datas, congrats blackest ! ;)


.
Right, the Light Value at the end of EXIF datas is Calculated,

the formula : LightValue = Log² ( Aperture² * 100 / ( ExposureTime * ISO ) )

keeping ISO at 100, changes to : ExposureValue = Log² ( Aperture² / ExposureTime ) @ ISO 100

I built an utility SW 1st written in Pascal Language... in Delphi-Kylix around year 2k...
Now that every Browser supports the JavaScript Math.lib...
I just rewrote it in HTML JavaScript :

Camera Simulator, Exposure Calculator, Scene Light Value -49 to 69 Ev-Lv.

Please :
- don't change Ev-Step from 1/3 to 1/2 or vice versa...
- don't change back Ev-Step from 1/2 or from 1/3 to 1 Ev...
until I have time to fix the errors giving Non-Normalised Values !

Enjoy ! :cool:
Forum: Pentax Q 04-09-2019, 03:10 AM  
Pentax Q for astrophotography beginner?
Posted By geo444
Replies: 84
Views: 18,688
.
Thanks kayakfari ! ;)
and now, how easy it is to restore the AutoFocus functional to infinity :
Pentax Q, Q-10 modified for IR-Landscape photography


.
what are your intended uses : Action-Cam like, Astrophoto, Landscape-IR ?...
or, enjoy your 12mm board mount lens on the Q ?
What is its Focal Length ?


.
As long as the lens doesn't show Chromatic Aberration, it's still good...
else, if your lens isn't Well Corrected, could be worse...
as you allow a wider Light Frequency Range through the lens
http://mecastronics.free.fr/PentaxQ10AstroIR.html

;)
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