Are all apertures the same???
Jul 4, 2018 00:23:29 #
IBM wrote:
Yea you may be right it sounds as you know very little and are asking the wrong questions ,like what is the fstop and what does it do when I change it , and what does a higher or lower shutter speed change your stop out come if your in manual , then there's iso how many years yo
Been with a camera , hang in there you will do ok
Been with a camera , hang in there you will do ok
Stop.... I didn't ask any of that. Just because someone doesn't know one thing, doesn't mean they don't have knowledge on anything. Clearly you don't see sarcasm. E Please don't respond to any of my posts..... One simple question and Steve Perry answered is kindly, accurately, and simply. You come across as a know it all, and I'm sure that was not your intention. IBM, thanks but consider the question answered...
Jul 4, 2018 00:40:17 #
IDguy
Loc: Idaho
swartfort wrote:
My "common sense" look at this tells me ... (show quote)
As noted above, the direct answer to your question is yes.
Please know that the aperture you see on the lens is the MAXIMUM aperture (minimum f-stop) the lens can achieve at the two ends of the zoom range. At any zoom you can adjust to smaller apertures, usually up to at least f22. Many feel that most lenses are sharpest at mid range of apertures; i.e. between f7 and f11. But often you’ll want smaller apertures, e.g. f 16, for more depth of field sharpness.
Jul 4, 2018 06:02:12 #
billnikon
Loc: Pennsylvania/Ohio/Florida/Maui/Oregon/Vermont
swartfort wrote:
My "common sense" look at this tells me ... (show quote)
Yes, 7.1 lets in the same amount of light on ANY lens you use. Same with all the other apertures. But, sometimes the best opening (apertures) are a few stops down from wide open. For example, if you have a maximum opening of 2.8, your sharpest openings would be 2-4 stops down, in this case, your best aperture settings would be 5.6 to f11. This is not always the case, but, generally, the lens is very sharp at these openings. Some lenses are very sharp wide open. But as a general rule I like to stop down my lenses several stops unless I am trying to eliminate back grounds.
Jul 4, 2018 07:04:53 #
IBM wrote:
There is other factors just be cause it's the same stop doesent mean your going to get more or less light . Your shutter speed for one among others
Swartfort's question - "Does a 7.1 aperture setting on a short tele lens allow the same amount of light onto the sensor as a 7.1 aperture setting on a long tele lens?" - is very clear, and has absolutely nothing to do with shutter speed!!! Why not say you have to consider ND lenses??? - and anything else to confuse the issue???
Loren - Baguio City
Jul 4, 2018 07:08:39 #
Jul 4, 2018 07:12:25 #
swartfort wrote:
Thanks for the condescension. The only thing that you KNOW what I don't know is the question I asked. I do KNOW your response was pompous and might be a CLUE why people hesitate to ask questions here. I am sure there are BOOKS on kindness and generosity that you could invest in. Maybe if I join a camera club I could run into someone as KIND as you face to face. To others who try to help. A sincere thank you.
>> Unfortunately, you'll have to get used to it. There is a small but vocal minority here who feel
compelled to trash anyone who is a beginner or novice, or even who has one question that they
interpret as the OP being insufficiently educated. Sometimes it seems like a competition
among a bunch of posters desperate to establish that they are more expert than the other self-
proclaimed experts. And on it goes.
To all of you (you know who you are) in the trashing group, I extend this invitation: Take a deep
breath, and get over yourself before replying. Remember that old adage, "DO UNTO OTHERS..."
well it still applies here. Moreover, if it's not something you would say to someone's face, then
don't say it here.
Next time you have the inclination to trash someone in a manner you think is oh-so-clever, ask
yourself these two questions:
(1) Is my comment respectful to the OP?
(2) Does my comment contribute anything of value to the discussion?
If the answer to either question (or both), is "No," type your whole comment in, take a moment
to reflect, and then delete it. Know why? Because no wants want to read your self-aggrandizing crap.
Respectfully,
Alan
Jul 4, 2018 07:19:40 #
swartfort wrote:
My "common sense" look at this tells me ... (show quote)
Seems Bill_de and Steve Perry answered YOUR question quite succinctly and correctly, 'nuf said.
Jul 4, 2018 07:50:42 #
swartfort wrote:
My "common sense" look at this tells me ... (show quote)
In theory YES, in practice probably very close variance due transmission factors of the glass in the lens
Jul 4, 2018 07:51:32 #
Jul 4, 2018 07:57:23 #
swartfort wrote:
My "common sense" look at this tells me ... (show quote)
For practical purposes f7.1 is the same exposure for whatever lens you use. That is why external hand held light meters work. They suggest and aperture and shutter at a specific ISO, you set your camera to that and the photo comes out right. That is the beauty and simplicity of the system as designed, otherwise it would be a burden and chaos. As some say there is a T stop system used for cinema and it is needed for that purpose but unless you are doing cinema production the small variation in lenses due to lens elements etc. creating minute fractional differences us normal people will never see a difference no matter how hard we try. Monitors vary more than the slight differences you would encounter.
Jul 4, 2018 08:03:31 #
Jul 4, 2018 08:07:58 #
swartfort wrote:
My "common sense" look at this tells me ... (show quote)
The aperture number is derived from a formula, using the measurements of the lens. As for the Auto ISO setting, there's theoretical, and there's practical. The only way to know for sure is to shoot with each lens.
Jul 4, 2018 08:24:14 #
swartfort wrote:
My "common sense" look at this tells me ... (show quote)
If you are OCD about exposure, the answer is an emphatic NO!
But for all intents and purposes, the differences for non- cinematic uses, the differences are small enough to not matter.
One way to test this would be to take the two lenses in question, and with the camera set to manual exposure and auto ISO. Take a picture focused at or near infinity with each The lens with better light transmission will show images with a lower ISO.
This is a simple explanation:
https://petapixel.com/2016/12/30/f-stops-vs-t-stops-difference-explained-plain-english/
Jul 4, 2018 08:35:08 #
swartfort wrote:
Thanks for the condescension. The only thing that you KNOW what I don't know is the question I asked. I do KNOW your response was pompous and might be a CLUE why people hesitate to ask questions here. I am sure there are BOOKS on kindness and generosity that you could invest in. Maybe if I join a camera club I could run into someone as KIND as you face to face. To others who try to help. A sincere thank you.
swartfort - thanks for pushing back on IBM. His comments just show his mind set. Manners and consideration go a long way. I have seen a some members on this forum with those kinds of unwelcome replies to a member asking an important question. If a member takes the time to ask a question on this forum they deserve a respectful reply. If we were all expert photographers, which I am not, we wouldn't need this forum. I was under the impression that the reason for this forum was to share our experience and learn from each other, not put someone down just because they ask a question. I have not been a member that long, but I have seen many responses by a few members that are just down right disrespectful. In the past I have just chosen to ignore them and move on. But I'm getting real tired of seeing negative comments and now I am pushing back. Not everyone is doing it, just a few. One member that I respect and enjoy reading her comments is Linda From Maine. She is always helpful and very respectful and there are many others just like her. I haven't looked into what the guidelines are for this form, but maybe there needs to be some if common
sense and dignity doesn't prevail.
Jul 4, 2018 08:45:59 #
[quote=IBM]
May you should also read some books on grammar & English to make you point more understandable, not sure if Time-Life has any of those....sure would help your snarky responses
swartfort wrote:
My "common sense" look at this tells me ... (show quote)
May you should also read some books on grammar & English to make you point more understandable, not sure if Time-Life has any of those....sure would help your snarky responses
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