Name: ジェミニ「ナノバナナ」の画像作成時のアスペクト比の問題を即座に修正する方法 (How to INSTANTLY Fix Gemini 'Nano Banana' Aspect Ratio Problems When Creating Images)
Uploaded: 2025-09-24T16:04:32.000Z
Duration: 7 min 36 s
Description: VoiceTubeの動画で発音を聞きながら英語表現を覚えよう！学べる英語：

So there is a known issue when you're creating or editing a picture with Gemini 2.5 plus image preview also known as Gemini banana.

Gemini 2.5 plus image preview（通称Geminiバナナ）を使用して画像を作成または編集する際に、既知の問題があります。

様態の副詞

Essentially it is difficult or maybe impossible to get the correct aspect ratio that is based on your prompt.

基本的に、あなたのプロンプトに基づいた正しいアスペクト比を得るのは難しい、あるいは不可能かもしれない。

Like in this example I want to get a 16 by 9 aspect ratio and yet the picture is square it should be a horizontal picture.

この例のように、16×9のアスペクト比にしたいのに、写真が正方形になっている。

How about this one I just provided a vertical picture and I want to add a hat into the cap and also I want to turn the picture to be a horizontal aspect ratio and yeah the final picture is still a vertical picture.

縦長の写真に帽子を加え、横長のアスペクト比にしたいのですが、最終的には縦長の写真のままです。

So this is a known problem with the Gemini not the banana and there is apparently no way you can fix this problem.

つまり、これはバナナではなくジェミニの既知の問題であり、この問題を解決する方法はないようだ。

And also what I find to be hilarious is this answer from Google health community which is official and basically there is a person having this problem and this is the answer which I find to be embarrassing and hilarious.

また、私が愉快だと思うのは、グーグル・ヘルス・コミュニティからの公式回答で、基本的にこの問題を抱えている人がいて、これが恥ずかしく愉快だと思う回答である。

So it says hi there and I understand your concern to guide Gemini towards a specific tone you should include explicit instructions within the prompt.

ジェミニを特定のトーンに導こうとするあなたの懸念は理解できるが、プロンプトの中に明確な指示を入れるべきだ。

Yeah that is a genius high-level answer that's just basically use that's exactly the things that people have tried and it doesn't work and it's just giving you this useless answer.

ああ、それは天才的なハイレベルな答えだ。基本的に、人々が試してうまくいかなかったことをそのまま使っているだけで、こんな無駄な答えを出しているだけだ。

So not even Google knows how to fix this problem apparently but there is actually a general fix on how you can create a picture or edit a picture with a specific aspect ratio and the way to do that is basically to provide a blank picture let's say you want to get a 16 by 9 aspect ratio picture you have to create a blank or empty picture with 16 by 9 aspect ratio and then use that to reference or to guide Gemini about the ratio that it needs to produce so it is actually quite a reliable way to get a correct aspect ratio but the problem is that you have to create multiple different pictures with depending on the aspect ratios that you want to get so you have to use Photoshop or maybe some other third-party tool to be able to create those blank pictures but actually there is a simple way to get that kind of file using Gemini AI and here's how you can do that so let's go to Gemini first and basically we want to create an app that can produce some blank pictures based on any aspect ratio so this is the prompt that you can use and don't worry I'm going to provide the prompt in the video description down below it's a very long prompt because again we want to create an app so click tools click create sorry click canvas and just send the message now depending on what or when you're watching this video it could be there could be a different version of Gemini and therefore the app might look a bit different but basically it should be still serving the same purpose which is allowing you to create some transparent PNG pictures with blank content but you can specify the aspect ratio so I'm going to wait for a bit it should be able to create the tool any second now it is actually quite a simple tool and there you go so the tool has been created and it looked like this again the interface or the UI could be different but more or less the function is the same so here I can select the aspect ratio like 1 to 1 4 by 3 3 by 2 16 by 9 and 21 by 9 but I can also manually select the aspect ratio now in this case I want to create a 16 by 9 aspect ratio picture so I'll select this and then click download PNG and as you can see I have this file there is essentially empty there is nothing here it's just a fully transparent picture there is no info about it except for the aspect ratio now we are ready to use this file to guide Gemini Nano Banana so let's go to Gemini again and I will try to edit this picture sorry to create this picture again which is a photorealistic picture of a frog riding a train in the 1950s I'm going to copy it now I'm going to paste that into this and I'm going to upload that transparent sorry that blank picture it is actually transparent I'm going to click it click open so it's just nothing there just no info about it and this is the extra instruction that you must provide when creating a picture don't worry I'm going to provide you the guide on how you can edit a picture using this technique now click tools click create images and send the message so you will see that it is not creating a vertical or square picture anymore it is going to be a 16 by 9 or horizontal aspect ratio picture so I'll wait still generating the image it should be done any second now okay there you go so the picture is definitely not square not vertical it is actually horizontal although there is this black bar but it's easy to fix and you can also just redo the process and maybe the next iteration will give you a complete picture but overall it is not it is following the proper it is following the instruction the instruction which is creating the picture based on the aspect ratio that we provided now how about editing a picture so it's actually quite simple and I will try edit this picture again the cat and I'm going to add a red hat to the cat so I'm going to go back to Gemini I'm going to upload this picture and now I guess I have to download oh sorry I still have that transparent for us sorry about that I still have that blank transfer and file okay and if I don't have to you know download another file now I'm going to this again upload files and then select that transparent picture the blank picture and this is the prompt that I will use make the cat wear a red hat just this prompt and paste that and this is the extra instruction that I'm going to provide to Gemini and don't worry all the prompts should be available in the video description down below including the prompt to create the PNG picture generator so this is the prompt use the second picture as the reference for final aspect ratio and fill the area that wasn't shown in the original picture click tools click create images and send the message so it's not basically you can specify it could be a second third fourth or maybe the first picture depending on the order when you are uploading the picture to edit the so in this case the second picture was actually their transparent picture and that's why I said it is a second picture okay just wait and there you go so this is not a crop picture is actually the details that are created by Gemini because again the original picture sorry the original picture look like this and yeah it is vertical and now we have a original picture so that's basically how I can fix Gemini not banana unable to create a picture based on the specified aspect ratio again all the prompts should be available in the video description down below thank you so much for watching and I'll see you on my next video have a great day

しかし、特定のアスペクト比で画像を作成または編集する一般的な方法はあります。アスペクト比の画像を作成し、それをGeminiが生成する必要のあるアスペクト比の参照またはガイドとして使用します。しかし、実はGemini AIを使ってそのようなファイルを入手する簡単な方法がある。Geminiのバージョンが違うかもしれないので、アプリの見た目が少し違うかもしれませんが、基本的には同じ目的である、空白のコンテンツを含む透明なPNG画像を作成することはできるはずです。アスペクト比は1対1、4対3、3対2、16対9、2