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Re: NPF Rule instead of the 600 Rules

Posted: 27 Jun 2015, 09:30
by djoubert
Hi,
Thank you again for your attention to improve this great application.
About the result for the npf calculation, the value is close of the value I use, ( 20s with a 6D full frame , 2.8 apperture, 14mm focal lenth )
nevertheless when checking from the npf detailled rule I dont get the same result.
I tried to understand from the link you provide above, but did not find the rule you applied.
Could you provide within this post the exact rule you implemented ?
Thank you very much
Dominique

Re: NPF Rule instead of the 600 Rules

Posted: 16 Nov 2015, 10:09
by fred_76
Hi!

I'm the author of the NPF rule. The link to the page with all details on the calculation and an online calculation tool is here :

http://www.sahavre.fr/tutoriels/astroph ... -d-etoiles

It is in french but Google should translate it quite easily for you.

The online tool uses the full NPF rule and not the simplified rule. It takes into account the elevation of the portion of sky you want to shoot. No need to use exact values, just use your hand with fingers wide opened to measure the elevation above horizon and indicate the approximate direction (North, South...). The result will be given in 9 portions of the photoframe so that you may focus on the right area of your composition.

The online tools already has the data of most DSLRs and digital backs (340 listed from 15 brands). I will try to keep it up to date at least once a year.

Clear sky

Fred

Re: NPF Rule instead of the 600 Rules

Posted: 16 Nov 2015, 13:22
by aaronpriest
fred_76 wrote:Hi!

I'm the author of the NPF rule. The link to the page with all details on the calculation and an online calculation tool is here :

http://www.sahavre.fr/tutoriels/astroph ... -d-etoiles

It is in french but Google should translate it quite easily for you.

The online tool uses the full NPF rule and not the simplified rule. It takes into account the elevation of the portion of sky you want to shoot. No need to use exact values, just use your hand with fingers wide opened to measure the elevation above horizon and indicate the approximate direction (North, South...). The result will be given in 9 portions of the photoframe so that you may focus on the right area of your composition.

The online tools already has the data of most DSLRs and digital backs (340 listed from 15 brands). I will try to keep it up to date at least once a year.

Clear sky

Fred
Thank you very much Fred!

Re: NPF Rule instead of the 600 Rules

Posted: 08 Apr 2016, 10:46
by fred_76
Hy, I updated the page, now 406 DSLRs and digital backs, from 19 brands.

All the best !

Fred

Re: NPF Rule instead of the 600 Rules

Posted: 01 Jul 2020, 00:55
by inbremen
Agreed!
but the NPF rules is quite stringent. there is also 300 rules, which is pretty acceptable for everyone. consider it please

Re: NPF Rule instead of the 600 Rules

Posted: 12 Dec 2021, 15:02
by videshik2
Hi there! Thank you so much for sharing this :)

Re: NPF Rule instead of the 600 Rules

Posted: 11 Feb 2024, 16:24
by mightymenorah
It's fascinating to see the variations in exposure calculations for different camera setups. Indeed, the numbers can vary quite a bit depending on the specific camera model, lens, and shooting conditions.

For instance, achieving an exposure time of 20.98 seconds with a 6D and 14mm lens sounds plausible, while obtaining 17.45 seconds on a 36MP D810 for the same setup is intriguing.

What caught my attention is the Rule 600 calculator in DslrDashboard, suggesting a significantly longer exposure time of 42.86 seconds based on the "Rule 600" and 4.80 seconds for the "real slowest shutter." It's clear that different tools and methodologies yield different results.

It's also interesting to note the different approaches people take, such as using a Rule 500 but subtracting 5 to 10 seconds, or utilizing the NPF rule and rounding to the nearest interval when not in bulb mode. These adjustments demonstrate the nuances and individual preferences in exposure calculation techniques among photographers.

In the end, it's all about finding what works best for each unique shooting scenario and personal shooting style. Experimentation and experience play crucial roles in mastering the art and science of photography.