Canon Eyes a Canon RF 50-150mm F2.8

[HMC11]

The problem is the lack of evidence or more importantly, Canon's internal testing where they decided that 19.96 was acceptable. I mean it's great that you did something that you consider to be worthwhile evidence but your test bed isn't Canon's test bed and your image analysis isn't Canon's image analysis.

I once had a colleague who, when confronted with scientific evidence from a wide range of disciplines about human's impact on global warming, simply stated that he wouldn't believe any of these results until he had personally conducted the experiments. All around the table simply disengaged from the debate.

 

[David_B]

I once had a colleague who, when confronted with scientific evidence from a wide range of disciplines about human's impact on global warming, simply stated that he wouldn't believe any of these results until he had personally conducted the experiments. All around the table simply disengaged from the debate.

I hear you. The evidence of one person that's demonstratably biased towards Canon is not good scientific evidence. It might be good evidence for him, but nobody else, it would be good if we had scientific evidence, but we don't. Even the description of the test does not fill me with joy over its rigour. I'd wager that Canon does have that evidence. (and possibly Adobe, et al.) Consider Canon witholding that evidence akin to oil companies witholding evidence from decades ago about their predictions of global warming.

 

[JensR]

The evidence of one person that's demonstratably biased towards Canon is not good scientific evidence.

Did you ever in your life see scientific evidence that was coming from an unbiased person?

 

[neuroanatomist]

The problem is the lack of evidence or more importantly, Canon's internal testing where they decided that 19.96 was acceptable. I mean it's great that you did something that you consider to be worthwhile evidence but your test bed isn't Canon's test bed and your image analysis isn't Canon's image analysis.

Worth noting that Canon was certainly not the first manufacturer to 'cut corners' (literally) from the image circle. The fact remains, the ultimate arbiter is the consumer. If you don't like it, don't buy it. Their choice to rely on distortion correction to fill the frame does not seem to be impacting their market share. The RF 16/2.8 appears to sell very well, for example. If you prefer 'optically corrected' lenses, stick with EF for your wide angles.

 

[David_B]

Did you ever in your life see scientific evidence that was coming from an unbiased person?

I don't know enough scientists to know, but I do know one thing - many scientists with bias towards an outcome will report findings that disagree with their predictions because the goal is knowledge, not to be right.

 

[neuroanatomist]

I don't know enough scientists to know, but I do know one thing - many scientists with bias towards an outcome will report findings that disagree with their predictions because the goal is knowledge, not to be right.

I know a lot of scientists. Most will report findings that disagree with their predictions. Some will not report them (in part, that's because what often happens is they predicted something would work and it didn't, and it's difficult to get negative data published). From the occasional retractions that occur, some very high profile, it's apparent that some will manipulate the data so that the findings do support their predictions.

 

[David_B]

it's apparent that some will manipulate the data so that the findings do support their predictions.

Some would argue that this isn't science. Being selective about the data ia also a way to get to that destination. grumble.

 

[axtstern]

At first look, my feeling was the same. This lens would complement Sigma's 10-18mm and 18-50mm very nicely. But it seems to be too large. I would actually expect (or, perhaps hope) that Sigma would come out with something more like a 50-115mm F2.8 that is more compact.

When I look at the table in the article it lests the lens length as:

176.15 (W) and 236.15(T)

I'm assuming these are in mm. When I look at the spects for the RF 70-200 F2.8 (non-Z) & F4 it lists the lens length as:

F4 : 119 (W) and 181(T) (https://www.the-digital-picture.com/Reviews/Lens-Specifications.aspx?Lens=1529)
F2.8 : 146 (W) and 212(T) (https://www.the-digital-picture.com/Reviews/Lens-Specifications.aspx?Lens=1417)

Which suggests that the 50-150mm would be longer than both of the current RF L non-z 70-200mm. Am I missing something? Is it just the diameter and weight improvements? Lower price? More versatile focal length range? It really doesn't seem to complete the "non-L f/2.8 trinity".

OOPs I did not read the dimensions.. The Sigma EX (non stabilized) of yesterday I used was a non extending internal zoom which had always 140 mm length and 67mm front element
The newer OS Version had almost 200mm and had a frnt lens of 77mm which made it useless when you looked for something compact.